What's the deal with helmets?

Commuters riding through the Vondelpark

The Dutch ride bikes more miles per person per year than any other country.  According to one Dutch safety expert, they have the lowest injury-accident rate on bikes than any other country.  With all the people riding, you hardly EVER see someone  wearing a helmet.  They DO crash, sometimes (rarely)-- I have seen it.  They ARE skillful riders.  (When you see the 3 year olds scooting along on two wheel bikes, you understand why!) Yet the safety expert estimates that if all Dutch riders wore helmets, there would be 1,000 fewer head injuries in the Netherlands each year!  So why don't they wear them?  I've heard a number of explanations-- vanity (messes up the hair), doesn't look cool, it's uncomfortable, too hard to manage carrying a helmet around all day when bike is your basic mode of transportation, and "we don't need them because we know how to avoid a serious fall."  The notion of a helmet law has actually been discussed in Parliment.  But I think the politicians are afraid to pass what would be an immensely unpopular and difficult to enforce law!  Maybe what it comes down to is people's sense of individual freedom and not wanting anyone to tell them what they SHOULD do! Part of the Dutch "live and let live" (or in rare cases die!) attitude?