For my generation, putting a seat belt on when you get into a car is a natural instinct. I do recall our family car's in the early 80's that did not have seat belts. How times have changed for the better.
My parents always told me when I was learning to drive, they weren't worried about me on the road, they were more worried about the other people on the road. I think the same applies to adults wearing helmets.
Clearly the same idea is not translated to riding bike's. I was under the impression it was the Law that everyone riding a bike must be wearing a helmet but that does not seem to be the case. Watching people in Riverside Park and Central Park riding their bike's, I just don't get when I see the kid's wearing helmet's and the parents riding behind without helmets. What's good enough for the kids isn't good enough for the parents?
I am really perplexed when I see people riding without a helmet. Isn't it safety first?