Anti-social Punishment
It's a fascinating experiment, but I don't buy the author's explanation for anti-social punishment. He's talking about punishing "rats/narks" (which is also a big social taboo here in USA), whereas all punishment in the experiment is completely anonymous.I think a more plausible explanation is status envy. Someone who is publicly altruistic, is likely to gain compliments and plaudits from others. This would then boost their status, and bring down the relative status of others. This is likely to engender status-envy on the part of others, and they act upon their status-envy by inflicting punishment on the do-gooder. It's worth mentioning that I've personally seen such behavior here in America as well, especially when wealthy individuals or corporations engage in altruistic acts.