I get what Trofo's saying too, I get heckling is part of the game (same as I get that for some players they're abusive, whatever) but it's never cool to pick on someone who's obviously not in the right frame of mind. I'm happy to insult all my friends all day long too, but the moment I know they're not able to take it, or they're already down, I'm not touching them. Picking on the weak? That's playground bullying. If the guy didn't know it, he would have admitted to it by now.
agree on this one, you can "insult" your friends, if they can handle it, and give you back "insults", it is a good game
but, if there is someone that cannot handle it, then you stop, because hurting someone should not be part of the game
on the other side, they are playing in public, should have some mental consultants, or someone to help them with it, because there will always be someone to bullying them, you have to know how to handle it on the pitch