It just occurred to me, too, that helmet laws may very well have increased the medical costs of motorcycle riding, simply because people that cave their heads in are much less likely to require medical care than those that break every bone in their body BUT they're skull.
Yes, there's some hyperbole there...but everyone I personally know who's ever ridden a motorcycle has 1) incurred at least a six-figure hospital bill, and 2) would have incurred NO hospital bill if they weren't wearing a helmet, as they'd have been dead at the scene. I suspect if anyone ever bothered to do a study of it, they'd be surprised at how much motorcycle helmets do NOT decrease medical costs...