Yeah, same question for me, too. Why not just wear it?
Honestly, I know it seems silly, there's always the whole, "Well, I could die walking across the street," controversy.. But don't you value your life? Seriously, why not just wear it?
I know this doesn't have much to add to the argument, because it's not riding, haha.. but there's a snowboarder that I used to fallow, and he recently fell WHILE HIS HELMET WAS ON, and got a pretty serious brain injury. He spent four months learning to walk and talk again, trying to regain his sight, and he is still regaining his short-term memory. If he wasn't wearing his helmet, his doctors are sure he'd be dead. And if he wasn't, I don't even want to know what sort of state he would be in.
Then again it could have been the helmet that threw him off balanced and caused the whole thing. Maybe there would not have been an accident if he had not been wearing a helmet. Or maybe if he did crash with out a helmet and his head was lighter he wouldn't have hit his head because he could lift his head out of danger faster.
Hypothetical the helmet saved my life is nonsense, there is no way to know for sure what would happen if the helmet was not on.
Air bags, seat belts, and helmets are no guarantee to safety but even worse they can and have caused injuries.