This research explores the sustainability of street markets to grant access to fruits and vegetables (F&Vs) to underserved communities in emerging economies. Specifically, this paper studies the impact of adding new street markets to satisfy the demand of end consumers in a real case. To do so, we developed a novel non-linear mathematical model to establish the location and number of street markets. This model, a variant of the competitive facility location problem, includes specific features of street markets, such as their itinerant nature and the dynamic shopping behavior of customers. To feed the model, we collected data from both primary and secondary sources: we surveyed the main competitors of the street markets (i.e., small, family-owned retailers or nanostores) to investigate their market share and purchasing habits. The problem was solved with an ad-hoc iterative method. The results suggest that street markets can provide better access to F&Vs to food-insecure households to some extent. Still, their management, operational complexity, and financial sustainability may limit their applicability in the long term.