Can They Make You Wear A Ski Helmet?

There are tons of great reasons for wearing helmets in this thread. I hadn't even thought of the one about minimizing the risk that my friends will have to haul an unconcious (or worse) me out of the woods if I brain myself....

I will throw my reason to start wearing a helmet on the pile:
I got a girlfriend, back in college, when the guy she had been dating prior hit a rock (inbounds, I may add) with his head.  He got tossed over his toes on a roller while fire-trailing with his buddies. Basically, she became available b/c her boyfriend now had the emotional capabilities of a 4th grader. 
I didn't have much money back in school, but I plucked down a good bit of it for a helmet when I learned why she was available. It's all about finding out what motivates us, I suppose.

While we're at it, let's require that the helmet have a brain in it.

Seriously, tho, I saw a news article on this a couple of years ago, stats approximate: At ski areas in the French Alps the injuries to under-18 skiers/riders were 80% head injuries. Then, when France started requiring helmet use for minors by law, those injuries all but stopped. Now, 80% of all injuries to that age group are to wrists and arms -- common snowboard injuries -- not the paralysis and fatalities of head trauma.