1. Introduction
In the recent years, the commerce of products and services through the internet expanded, with the pandemic having greatly contributed. E-commerce evolution made companies consider new strategies exploring innovative information on specific platforms to better understand consumer needs and to support their decision-making [
1,
2]. In some cases, consumer income was also affected by the pandemic and therefore, at least impulse shopping was reduced as consumers considered a potential risk, while in the case of scarce products, consumers understand the value of the products and perceive them as unique thus their willingness to buy increases [
3,
4]. During the pandemic, online sales have proven to be an effective sales channel for companies to maintain their sales, including agro-food products, despite several businesses having had to shut down, especially in the second quarter of 2020. Studies have demonstrated that small businesses need a lot of support from government to better adapt to the online environment [
5,
6,
7].
The COVID-19 pandemic affected several aspects of social wellbeing, including food security and global trade, which created a context of uncertainty regarding the sustainability of food placement, and products became more sensitive to costs and price changes. The need to support agrobusinesses in the process of implementing eco-efficient actions has proven critical and post-pandemic strategies are required [
8,
9,
10]. The same awareness of sustainability regarding the need for responsible consumption and social responsibility is demonstrated by studies pertaining to conscious consumption incorporated in a behavioral change, as well as those considering the social learning towards social change [
11,
12]. Moreover, several studies, show that COVID-19 not only increased the interest in online sales and responsible consumption, but also affected the online purchasing behavior of the consumer segments, including the green product purchase attitude and the attitude towards certified food providers. Some studies show that purchase intention is related to perceived risk, wherein reduced risk would increase the purchase intention [
13,
14,
15,
16].
The current post-pandemic context is still affecting online businesses; both small and medium enterprises, as well as large companies, must re-evaluate their options and marketing strategies according to the type of industry they are in. Recent research demonstrated that satisfaction is one factor influencing customer online purchase intention in the small business environment. Brand trust is still impacting online purchasing intention and business management should invest in their corporate social responsibility image to increase customer trust [
17,
18,
19].
The online marketing cost is reflected in the pricing of the online advertising, measured as cost-per-click, which is typically considered by the brand retailer. Cost-per-click are charges for displaying advertising but in some cases losses are inevitable, as click behavior is unpredictable [
20,
21,
22]. However, what the role of online purchasing intention in the sale of the sustainable products is, and how the online advertising cost relates to sales, is still unclear. This gap between the declared action on one hand and concrete behavior on another hand is observed in the 2022 report on the progress of the sustainable development goals (SDG) which includes 12 goals dedicated to responsible consumption and the production of relevant statistics; for example, 83 new and a total of more than 400 policy instruments, over 60% of large companies having a sustainability report published in 2021, and a national preoccupation to stimulate the acquisition of environmentally sound and energy-efficient products [
23].
The aim of the current study is to demonstrate the relationship between the online sales of sustainable products and the online marketing costs in Romania in the last three years, considering the role of the online purchasing intention of customers. The study is based on a sample of companies and products in three industries considered highly open to sustainable approaches, namely electronics, home and garden, and clothing and footwear. Two research questions are defined: 1. How can online advertising costs relate to sales of sustainable products and the customer purchasing intention? 2. How can online purchasing intention for sustainable goods relate to online sales? The originality of the study is generated from the three areas of sustainable products and the online consumers’ purchase intention in Romania covering the last three years which mean before, during, and after the pandemic period. The results will provide adequate understanding of this variable relationship for the near-future decision-making of entrepreneurs in the sustainable production field, as well as for marketers to support future budget allocations for online advertisement. Moreover, the paper can support policy makers in their decisions to stimulate responsible consumption of sustainable products in Romania. Lastly, the research provides a literature development in the field of online marketing and responsible consumption and production.
The next sections will describe the theoretical background of the concepts used in the paper, starting from recent approaches covering the pandemic period (
Section 2), followed by the research methodology, including the hypothesis generated from the literature, the research structure model, and the statistical approach (
Section 3). In the end, results will be particularized to clarify how online advertising costs relate to sales of sustainable products and customer purchasing intention and how online purchasing intention for sustainable goods relates to online sales in Romania (
Section 4). Conclusions to the theoretical approach and the results achieved will be also outlined (
Section 5).
4. Results
The results are described for every step.
4.1. Step 1. OCC–OT Relationship
The linear regression showing the relationship between OCC–OT is presented for the first industry, electronics, in
Table 3; it demonstrates that at an R Square (R
2) which equals 0.6253, 62.5% of the variability of OT is explained by OCC. In addition, correlation R equals 0.7908 which shows that there is a strong direct relationship between OCC and OT in the electronics industry. ANOVA results are shown in
Table 3.
For the other two industries, the results show a very weak reversed relationship with an R Square (R
2) which equals 0.2022 and a correlation (R) of −0.1422, meaning that only 2% of the variability of the OT is explained by the OCC in the home and garden industry, and a very weak direct relationship with an R Square (R
2) which equals 0.3406 and a correlation (R) of 0.1846, which means that only 3.4% of the variability of the OT is explained by the OCC in the clothing industry, as shown below in
Table 4 and
Table 5.
4.2. Step 2. OCC–OPI Relationship
The linear regression showing the relationship between OCC and OPI is presented for the first industry, electronics, in
Table 6, and for the other two industries in
Table 7 and
Table 8.
The linear regression showing the relationship between OCC and OPI in the case of the first industry, electronics, demonstrates that at an R Square (R2) which equals 0.8382, 83.8% of the variability of OPI is explained by OCC. In addition, correlation R equals 0.9155 which shows that there is a very strong direct relationship between OCC and OPI in the electronics industry.
In addition, for the other two industries, the results show a strong direct relationship with an R Square (R2) which equals 0.582 and a correlation (R) of 0.7629, meaning that 58.2% of the variability of the OT is explained by the OPI in the home and garden industry, and a moderate direct relationship with an R Square (R2) which equals 0.1733 and a correlation (R) of 0.4163, meaning that 17.3% of the variability of the OT is explained by the OPI in the clothing industry.
4.3. Step 3. OPI–OT Relationship
The linear regression showing the relationship between OPI and OT is presented for the first industry, electronics, in
Table 9, and for the other two industries in
Table 10 and
Table 11.
The linear regression showing the relationship between OPI and OT in case of the first industry, electronics, demonstrates that at an R Square (R2) which equals 0.7291, 72.9% of the variability of OT is explained by OPI. In addition, correlation R equals 0.8539, which shows that there is a very strong direct relationship between OPI and OT in the electronics industry.
In addition, for the other two industries, the results show a moderate direct relationship with an R Square (R2) which equals 0.1792 and a correlation (R) of 0.4234, which means that 17.9% of the variability of the OT is explained by the OPI in the home and garden industry, and a very strong direct relationship with an R Square (R2) which equals 0.7827 and a correlation (R) of 0.8847, which means that 78.3% of the variability of the OT is explained by the OPI in the clothing industry.
4.4. Step 4. OCC–OPI–OT Relationship
This phase is conducted if the first three relations reveal significant relationship between the variables: OCC–OT, OCC–OPI, OPI-OT. If not, the mediation effect is not possible. Although steps 1–3 were conducted for all industries, only electronics showed a strong or very strong relationship between the variables. Consequently, step 4 will be considered for the electronics industry only. The results of the multiple regression are shown in
Table 12,
Table 13 and
Table 14 below.
The multiple regression indicates that there is a very strong collective significant effect between OCC, OPI, and OT in the electronics industry for the sustainable products.
5. Discussion
The results of the data analysis are synthetized in
Table 15.
Sustainable products in Romania have generated a clear relationship between the variables influencing the online transactions. However, there is a relationship difference in the selected industries, as consumers’ intention demonstrates a different relationship in the electronics industries from the home and garden and clothing industries. The regression analysis has shown a clear mediation model of the online purchase intention of the relationship between online campaigns costs and online transactions only in the electronics industry.
Considering the hypotheses, strong or very strong relationships have been confirmed, as following:
OCC–OPI only in the electronics industry (H1 confirmed);
OCC–OPI in two industries: electronics and home and garden (H4 and H5 confirmed);
OPI–OT in the electronics industry and the clothing industry (H7 and H9 confirmed);
OCC–OPI–OT only in the electronics industry (H10 confirmed).
The results are in line with other studies for the electronics industry. Firstly, the costs in the electronics industry are considered a primary element of a transaction, because they do not include the cost of production or of shipment, as has been demonstrated in the electronics market. In addition, digital products represent the main interest of men (35.7%), while utilitarian products represent the main interest for women (30.8%), which might be associated with the electronics and home and garden industries [
73,
74]. Secondly, most studies on sustainable products include analyses of products directly and demonstrate an interest of the consumers to buy sustainable products; however, research has demonstrated that the consumer interest on sustainable products in physical store is more declarative, i.e., consumers expressing their intention without effective purchase following it. Moreover, predictive analytics and testing 3D digital samples prior to production are used by companies to improve their sustainability targets [
75,
76]. Thirdly, the intention to purchase sustainable products with sustainable packaging is a reality which shows the interest of the young generation to buy not only sustainable, but to buy online; this is also in line with the findings showing clear evidence in the electronics industry [
77,
78,
79]. Fourthly, the online purchase intention in the electronics industry is also strongly influenced by the online campaign cost. This is like the findings in other studies analyzing online shopping behavior and revealing the importance of marketing strategies and the intention to use internet marketing [
80,
81].
Regarding the other two industries, where the mediation effect of the online purchasing power has not been confirmed, further research should be conducted. However, in the case of the clothing industry, it has been demonstrated, based on empirical evidence, that there is a strong positive relationship between online reviews and consumer purchasing intention and not the cost of the online campaigns, as well as a moderately positive relationship between trust and the consumer purchasing intention [
82].
The results show a type of behavior that is different in the case of electronic products from the behaviors specific to the other two industries, with a clear effect of the online campaign costs on the online transactions mediated by the online purchasing intention. The mediation effect is not confirmed in the case of the other two industries since consumers might still enjoy trying or touching physical products [
83].
6. Conclusions
6.1. Theoretical and Practical Implications
The research contributes to the theoretical knowledge of the main concepts, namely sustainable products, online campaign costs, online purchase intention, and online transaction, and reveals the importance of online purchase intention in the context of online trends regarding sustainability issues in Romania.
The pandemic supported the online environment in all kinds of transactions, but moreover, it increased the awareness of sustainable products. The findings presented in this paper show that online transactions are more influenced by the online costs and the online purchasing intention in the electronics industry, whereas, in the case of the home and garden and clothing industries, a moderate and weak relationship was shown.
Managers of marketing campaigns in advertising agencies can improve their efforts in better supporting the brands by accepting the differences in the industries and focusing not only on product characteristics communicated to potential clients but also on creating different campaigns based on the differences in the relationships between the parameters in each industry.
Brand managers of sustainable products in electronics can also consider the role of the online purchasing intention and pay attention to the campaign cost level which directly and strongly determines the online purchasing intentions of their customers. Therefore, the higher the marketing cost allocation becomes, the higher the online purchase intention gets.
Managers in the home and garden industry and the clothing industry can benefit from the findings in the sense that the relationship between online costs and their online sales are not strongly related and they should be aware of the fact that their online efforts might become profitless.
6.2. Limitations of the Research and Future Research Development
The study has a few research limitations: it does not consider the online cost per type of the campaigns, so relationships between parameters might be different in the case of search, shopping, display, and other types of campaigns. Another limitation is that the study applies to the eleven companies selected in the research, and the number of the companies could change the relationship between parameters. Thirdly, the study covers the pandemic period and some of the behaviors (such as the online one) had been displayed during this unique worldwide crisis situation. The considered period of time relates to the period of 2018–2022 which includes a mixture of data: The period before the outbreak of the COVID-19 pandemic, the peak period of the pandemic, and the period after the peak of the pandemic to the present. A more detailed analysis could be conducted in the future by dividing this period from a behavioral point of view and analyzing the consumers’ purchase intention and the online sales before, during, and after the pandemic. In addition, the pandemic period forced people to react differently from a non-pandemic period and to become more open to online sales, in general. Once the pre-pandemic context returns, it is more likely that consumers will return to previous behaviors, but this cannot happen entirely, since the online shopping has already been more and more integrated in their regular transactions.
Further research might include a generational analysis of the online purchase intention of sustainable products, an empirical study of sustainability awareness in Romania, an online campaign-based approach of the purchase intention regarding the sustainable products, and a comparative study between different countries, so as to better understand the characteristics and determinants of the purchasing intentions of sustainable products.