Food retailers are powerful actors of the agro-industrial food system. They exert strong lock-in effects that hinder transitions towards more sustainable agri-food systems. Indeed, their marketing practices generally result in excluding the most sustainable food products, such as local, low-input, small-scale farmers’ products. Recently in Belgium, several initiatives have been created to enable the introduction of local products on supermarket shelves. In this article, we study three of those initiatives to analyse if the development of local sourcing in supermarkets opens up an opportunity for a transition towards more sustainable agri-food systems. We conceptualise transitions as a shift in governance and ethical values and adopt a pragmatist approach of ethics combined with the systemic perspective of transition studies, to evaluate the impact of these initiatives. Our analysis shows that they mainly contribute to the reproduction of the incumbent agri-food system. It also highlights that first, to be a driver for sustainability transitions, food ethics need to be systemic i.e. relate to a systemic understanding of problems and perspective of sustainability, including social justice. And second, it highlights that governance arrangements involving not only representative organisations of the various agri-food and non-agricultural actors, but also actors upholding ethical values that are currently missing in conventional supply chains and representing excluded and marginalised interests, favour the uptake of such systemic ethics by incumbent actors. Hence, systemic ethics and inclusive governance are key features for initiatives to contribute to a sustainability transition.