Consumer behaviour is at the very heart of marketing. In the context of marketing, being a consumer implies that we are part of society and have some level of disposable income to buy goods and services that meet our needs and wants. According to T. Jackson (2004: 12), there are three theoretical approaches to understand, predict and explain consumer behaviour from sustainability perspective: rational, psychological and sociological. Some earlier studies on consumer behaviour and sustainability mostly relied on functional benefits and affordability of products and services, while according to F. M. Belz and K. Peattie (2012: 86–92) a broader approach to rational consumer choice is the concept of perceived benefits and costs. Perceived costs involve price, search costs, transport costs and time to prepare products (such as food). The rational school of thought puts emphasis on people’s understanding of sustainability issues, as well as their willingness and ability to pay any environmental or social premium that may be involved in sustainable purchases (Olli, Grendstad, 2001: 181–208). The theory, however, implied a market segmentation based on age and socio-economic groups. This simplistic segmentation approach led to the reporting of many conflicting outcomes and led to the conclusion that demographic segmentation is not the most suitable.