Supermarkets have been criticized by nongovernmental organizations (NGOs) for pricing tactics that trigger overpurchase, which may subsequently lead to food waste. Some retailers have responded by abolishing price promotions. However, is it the macro-level of the market structure, or the micro-level of the consumer, that is to blame for food waste? With an outset in consumer responsibilization theory and through 24 in-depth qualitative interviews, we explore how consumers and institutional actors perceive the responsibility for food waste in the interface between retailers and consumers, and how this perception has evolved. We identify two responsibility narratives—one that portrays the consumer as a self-governed actor and the other as interdependent on the institutionally shaped context. We uniquely show that over time, a process of hybrid responsibility expansion has led to an extension of the consumer's responsibility into the retailer's domain of action, and vice versa. Findings highlight that responsibilization is not either on the consumers or retailers' side and can expand for both. This provides a nuance and a new contribution to the theory. For businesses, our results imply that abolishing price promotions does not align with consumer's ascription of responsibility. In turn, actions that involve collaborations of actors, including consumers, speak much more to the perception of responsibility expansion.