The food bike (voedselfiets) project in the city of Hengelo (Netherlands) was designed to stimulate citizens to separate organic from residual waste. The food bikes take standard routes with designated stops to collect food waste from residents in high-rise neighbourhoods, which lack space to separate organic waste in garbage containers. Data were collected by a mix of qualitative research methods, which allowed to develop a holistic and contextualized view of the reasons why citizens joined this environmental initiative. The from literature well-known factors of idealism and self-interest can partly explain participation in the food bike project, but we have found that a habitus of not wasting food and social needs are also important reasons for people to participate. Especially older people take part in the project because the food bikes suit their habitus of frugality. The social interaction-behaving in a desirable way in the eyes of neighbours, and chatting at the bikes-stand in marked contrast to collection of waste by garbage trucks, in which contact is avoided as much as possible. The social aspect was reinforced during the Corona crisis, when indoor social contact was discouraged by the Dutch government. As it is, municipal efforts to promote pro-environmental behaviour build on the idealism and perceived self-interest of citizens, but could also make use of the social and emotional considerations of prospective participants and their attachment to the neighbourhood.