All I have to say is, you are an idiot not to.
For every, "My friends, Dad's, brother would have died if he had worn a seatbelt." story you hear there are probably about 500 "If they had worn a seat belt, they would still be with us." stories.
I am glad to see that the polls show that most of you escapists are not complete idiots. To the rest of you... I hope you are into some extreme sports, otherwise you are just risking death pointlessly.