Since 2011, many food cooperative projects have been developing in France. The design work of the food coop "La Louve", which opened in Paris in 2016, aroused a deep interest and led to the spinning off in several big cities of France. The objective of this paper is to explore the conditions for emergence of these food coop. On the basis of surveys of members of the food coop "La Cagette" at Montpellier, we will describe the sociodemographic profiles and motivations to get involved in the creation of such projects and in new forms of consumption. A questionnaire sent to the members in June 2016, supplemented by a qualitative investigation, allow to identify a variety of forms of commitment and representations on the project's objectives. We show that there are several levels of commitment (from the very committed project leader to the simple support) and that these affect consumption practices and motivations to engage. The more members get involved, the more they consume products distributed by the food coop, but at the same time the less they consider that the main purpose of the project is consumption. The members who participate more frequently tend to express political motivations (fostering social ties, living together, building alternatives) whereas the less active members think of the coop as a place of consumption. These results call to deepen the effect of the participation on the practices of consumptions, in particular the way the implication of the members in a role of prosumer can bring them to change their practices at the same time as their representation.