The determinants of human cooperation have attracted a lot of research in the social sciences. One commonly cited reason why individuals cooperate with each other and respect social norms is the threat of being sanctioned by others. But, if sanctioning is costly, why do people resort to it? One possibility could be that punishing those who violate social norms adds to an individual’s “social image”. We present evidence from a natural field experiment investigating whether punishers of norm violators enjoy social benefits in one-shot interactions. For the purpose of the experiment we had a team of assistants enact norm violations and acts of punishment and we recorded the reactions of observers in train stations in Germany. We find that punishers are not rewarded, while norm violators are punished by means of receiving less help from their environment. Men and women are treated in quite different ways.