The volume of food waste is increasing, and research has highlighted the issues related to its disposal methods. Disposers are emerging as a solution for food waste recycling; they are already used in various countries. Only a limited portion of solid waste discharge has been permitted depending on the infrastructure capacity. Although additional administrative costs are required to adapt the existing food waste disposal system to include disposers, research on consumers’ willingness to pay (WTP) for such changes is lacking. Therefore, this study analyzes consumer WTP to increase the capacity of infrastructure. In this study, contingent valuation methods are employed to evaluate WTP, and data are collected based on a one-and-one-half-bounded dichotomous choice model with 1155 residents. In addition, this study considers the relevant knowledge, satisfaction, and expectations of the service. The results show that the average WTP for additional sewage rates is KRW 6860 (USD 5.2). Covariate models show that knowledge of water quality and awareness of the extent of untreated sewage discharge during rainfall in CSOs significantly influence WTP. Additionally, satisfaction with sewage odor, expectations regarding sewerage fees, and concerns about preventing sewer backflow impact WTP. However, satisfaction with the disposer does not significantly affect WTP. Additionally, a regional analysis is conducted to determine the priority of regional infrastructure improvements. In Incheon and Seoul, where the number of complaints was higher than the average, WTP showed a positive influence. The findings of this study have practical implications for policymakers, as they can be used to determine regional policy priorities.