A word about reenacting and LARPing: They are not the same. Reenacting is an attempt to recreate an actual era in history. Authenticity is important in reenacting, since if you do something not in keeping with the era you're trying to portray, (wearing sneakers with your toga, for example) you're not doing a very good job. LARPing is not, and shouldn't be, held to the same standards of authenticity for the simple reason that LARPing is trying to create a fantasy atmosphere, not a historical one.
If you LARP, sooner or later you're going to have to resort to in-game violence (or somebody else will) and you'll find yourself in the middle of a combat. Now what? In the real world, you poke or smack (and get poked or smacked by) your enemy until one of you either runs away, surrenders, or is rendered incapable of resisting. In a LARP, though, it's more complicated than that.
So who hasn't, after a particularly rewarding game of Truncheons and Flagons, sat with their gaming buddies and fantasized about how cool it would be to slay dragons "for real?" Many of us get over these fantasies about our fantasies, or else they remain compound fantasies that we'd never actually do anything about. But for some, the lure of getting dressed up in silly clothes and whacking each other with sticks is too overpowering to resist, and thus was the LARP (Live Action Role Playing) phenomenon born.