I think you've completely missed the relevant issue in Michigan, which is that we are one of the few states with no-fault insurance and a lifetime catastrophic claims clause.
Because of this, the extra fee assessed on *every* vehicle insured in MI has increased from $14 ten years ago to $145 this year (and up from $108 only 3 years ago). Here's the data from the group that keeps the fund going that pays for all this long-term care:
http://michigancatastrophic.com/Cons...9/Default.aspx
http://michigancatastrophic.com/Link...%3d&tabid=2943
No helmet may not make for more crashes, but it is more likely that an accident will result in an injury requiring long-term care.
Again, as long as I have to pay the cost for your choice, no thanks. Pay for your own consequences (responsibilities and rights together) and you can wear a hat with nails pointing inward if you like.