Purpose – Customer misbehaviour, i.e. behaviour within the exchange setting that deliberately violates the generally accepted norms of conduct in such settings pose a problem for service organizations in several ways. Hitherto much research on customer misbehaviour has focused on psychological explanations and individual characteristics. This study broadens the perspective by taking structural factors of the service system into account. The purpose is to complement the existing literature on customer misbehaviour by investigating how the design and functioning of the service system influences the prevalence of customer misbehaviour. Design/methodology/approach – A critical incident technique was adopted to collect and analyse qualitative data from frontline employees who work on board buses, trains, trams and in metro in the Swedish public transport system. Findings – The study shows that many incidents are triggered by features of the service system. Specifically, three dimensions (service regulations, service resources, and service practice) of the service system are brought forward. The study suggests that customer misbehaviour is caused by an inherent paradox between pre-planned, standardised, mass service solutions and ambitions to adopt a customer orientation. Originality/value – By bringing forward the interactive role of the service system and its functionality the study complements previous research and contributes to a more complete understanding of customer misbehaviour, in particular within the context of system dependent services.