Wow, it amazes me at how many stories you guys have of people totally invading your personal space. Maybe it's my Canadian manors, or the fact I learned as a kid playing Warhammer 40000, that you don't touch other people's art without their permission, but I've never touched someone's cosplay, CERTAINLY not punched anyone. I've only been in full cosplay once, and didn't have anyone do anything rough to me, but I probably could have found a better path to get through PAX Prime then straight through the middle of a crowd. Not sure if someone said it, but my suggestion is pick your venue. Dragon Con is a high cosplay environment, people (or at least most) know the protocols. Your friend's halloween party, might not be the best, especially if there is drinking, most "normies" don't no the process that goes in to building something awesome, so they might not realize they're yanking on hot glued foam, not welded metal.