Same two sources (lunatic Palin-hating bloggers from Alaska) that have pushed reams of insane stories about Palin faking her pregnancy with Trig, that Palin is a cocaine-snorting crack whore, that Todd has a sideline as a pimp, that Sarah was under imminent federal indictment, and various other delusional nonsense.
Even if there were any truth to the story about a brawl (or more likely, a minor incident blown into ludicrous proportions), it would only enhance my positive feelings towards the Palin clan!
Your sentiments align with mine. This sounds like a fantasy pushed by a couple of lefty bloggers who took a 'germ' of something that happened and then went to town with exaggerations.