As Ron White put it:
I believe I read in the AJC today that old Ben had decided he'd be wearing a helmet if he ever got on another motorcycle.
Nothing new here. I see other idiots riding with short pants, sneakers, t-shirts etc. They may not really be idiots, but have yet to feel what it's like to lay a street bike down. A few hours in the ER getting gravels, bottle caps, glass fragments, beggar's lice, dried dog feces and used tobacco cuds dug from the top half inch or so of your hide followed by a few weeks of fighting the inevitable infection(s) is a learning experience many people will heed after only one time. Sort of like mashing your face flat and knocking out all your teeth can help you learn to wear a helmet, since the facefulls of lit cigarette butts, Japanese beetles, mouthfuls of gnats, and rocks kicked up from the road didn't give you a hint.