You should definitely have the choice as an adult, BUT should you sustain serious injuries caused by not wearing it then you should NOT be covered under the public health system. The ones who do wear them shouldn't have to fork out for others' stupidity.
JLM, It has been proposed that those who refuse to wear helmets or safety gear pay a premium for doing so. I have no issue with that. If you are willing to go out of your way and sign the disclaimer that says you do not plan to wear a helmet, then so be it..
On the seat belt issue, that is quite a bit more dicy.. In the olden days I would have agreed.. But in todays vehicles that have more airbags then screws I have to say the sealbelt is more of a hazzard.. I was recently hit from behind and would have had no personal damage had it not been for the seat belt. Hence I cost ICBC money due to a seat belt..
That said, I believe in wearing my seat belt for other reasons..
Sorry for going off topic..