I think the reason they're being made fun of is because of precisely the reasons you mentioned. No one is quite sure what it is they're talking about, they don't seem even seem to agree half the time. That said, I haven't seen a lot of the news coverage on it, so I might be a little off base.

But mostly I think it's that. That, and the teabagging. It's very hard to stop laughing when people keep crying out TEABAGGING! I can't undersatnd how not a one of them sat the others down and went, "uh, guys...no."