Facebook Status Arguments

What is the deal with getting in arguments about people's status messages on Facebook? I've chanced to see someone post, "Prez obama sucks!" receive thirty+ responses. These responses range from, "right on" to "I don't think you have considered all of the facts when making such an odious and ill-informed statement, sir." In either case, they are still responding to what amounts to a grammatically-terrifying drunken shout in a bar. I don't think it these statements (if one can be so generous to call them that) need to be debated, because there is nothing inherently debatable about them.

It seems, at first glance, there would be better forums for this type of rancorous debate, but maybe not. I think what confuses me most about the debates, or "firestorms" these statements evoke is how people, who one would assume know each other (it is Facebook, after all) can seemingly get away with the things they say that would normally require a good boot to the head if said in the real world.

People have often argued the reason people are such assholes online, and not in physical interactions with other humans is due to the perceived sense of anonymity. This kind of reasoning isn't without flaws (IE if people think they are in any way anonymous online, not only are they naive, but a good case could be made that they must suffer from some form of brain damage) but the whole idea of Facebook is to remove anonymity. The goal is to let people know who you are so they can seek you out and communicate directly with you. So, how do they get away with calling their wives a bitch or blatently disrespecting friends and family without any consideration of the consequences? It's a strange phenomenon.