What would fluther-style moderation look like in the real world?

Suppose there was a function for a moderator in in-person life that works something like the way a fluther moderator works on fluther? What situations would that moderator fix? How would they fix them?

Take bullying, for example: what if we had playground moderators to deal with it? Or moderators wherever there is bullying? How would that work?

What other situations would you want a moderator in? How would they work? Would there be any negative consequences to having real world moderation?