In my opinion, it's not really needed that often; I do get mad, but some people are ignorant and just don't understand how people in a good society should act.
Now, if the person is going out of their way to be a scumbag, or if they're just taking things too far, that might be appropriate. In situations like this, revenge is an extremely enjoyable act, and I won't hesitate to act out and do something extreme to get them to stop being a moron.