Antecedents and consequences of service staff’s advice-giving frequency on diners’ overordering behavior

Within casual dining restaurants that provide table service, more than a third of food waste is associated with customers being unable to finish the food on their plates. Service staff can play a crucial role in reducing food waste in these establishments by offering diners timely advice; however, this topic has not received sufficient attention from researchers and practitioners. This study aims to explore the antecedents of restaurant service staff's advice-giving frequency and its impact on diners' overordering behavior. Additionally, it investigates self-efficacy’s moderating effect. A total of 309 restaurant service staff were recruited to complete the survey. The findings reveal that moral obligations, environmental concerns, green self-identity, and perceived job insecurity influence staff's advice-giving frequency, which, in turn, reduces diners' overordering behavior. Furthermore, the relationship between advice-giving frequency and overordering behavior is moderated by staff's self-efficacy. The practical implications of this research are discussed.