Social Norms, Expectations and Sanctions

Hindriks' paper raises two issues: one is formal and concerns the notion of 'cost' in rational choice accounts of norms; the other is substantial and concerns the role of expectations in the modification of payoffs. In this commentary I express some doubts and worries especially about the latter: What's so special with shared expectations? Why do they induce compliance with norms, if transgression is not associated with sanctions?.