Well posting from my phone so I tried to keep it short, but I don't wanna be the guy that just says something sarcastic because he doesn't have anything else to say.
#1. Obviously wearing a helmet is safer. But not riding at all is even safer yet.... However we still choose to ride. I know that sounds like I'm being sarcastic, but I'm being serious. It's all about personal risk in relation to reward. For me the risk of riding sensible while wearing a helmet is low, therefore the joy (reward) of riding outweighs the risk and my choice is made. Someone else might love the feeling of the freedom of riding without a helmet. Maybe they don't have a family, and riding is their true passion. The reward of riding without a helmet may outweigh the risk for this person.
It's kind of like wearing a condom. Everyone knows it's the safest, but does everyone wear one 100% of the time.... Obviously not. The reward (better sex) out weighed the risk (pregnancy, stds, etc)
#2. Insurance. Insurance rates aren't based on the number of deaths or accidents. It's based on dollars paid out, period. A 7k bike is nothing for an INS company to pay. What kills them is medical bills. I would venture to say they pay more in medical bills to people WEARING helmets than they do to people not. If you die in a wreck, they have no medical bills. And even if you live but are severly injured, they are protected by a cap (usually 100k) limiting their medical liability. I know plenty of people that have racked up tens of thousands of medical bills from a wreck when they were wearing a helmet. The few bad wrecks I know of with no helmet resulted in 0 medical bills due to death....
Now don't get me wrong I believe in wearing helmets. I won't ride without one. But our freedoms of choice are becoming few and far between. Don't be so quick to give up one of the few we got left.