The transformation of traditional food markets into urban tourism destinations has garnered increasing attention, yet the mechanisms driving tourist motivations remain underexplored. This study addresses this gap by proposing a host–guest sharing model grounded in the Theory of Self-Regulation (TSR). Employing a mixed-methods approach, we first conducted grounded theory analysis on 358,700 words of travelogues, identifying six TSR-based constructs: host–guest sharing, sense of place, behavior attitude, desire, subjective norms, and behavioral intention. These constructs were then validated through structural equation modeling (SEM) using survey data from 416 tourists. Results indicate that host–guest sharing (β = 0.925) and sense of place (β = 0.947) are the primary drivers of tourist intention, mediated by behavior attitude (β = 0.662) and desire (β = 0.861). Subjective norms (β = 0.724) further reinforce intention formation. The findings highlight the centrality of authentic cultural experiences and resident–tourist interactions in shaping food market tourism. This research extends the TSR framework by integrating geographical and psychological perspectives and offering actionable insights for urban planners to enhance food markets as sustainable tourism attractions through improved service quality, cultural storytelling, and equitable space design.