Personally one needs his/her head examined for not wearing a helmet. It is not remotely close to a seat belt law. It is more requiring a seat. Hit the brakes hard at 5 MPH in rainy weather stopping on the large crosswalk paint . Bike was on the ground in NY second, head slammed the pavement. Instead of a trip to the hospital and head fracture I righted the bike shaking and unhurt thanks to my helmet.
For you riders not wearing a helmet religiously please have your organ donor card current and life insurance for family. You spend good money on leather, boots and glasses why not the most important safety apparell? As hazardous as motorcycle riding is most head injuries are preventable using a good DOT helmet.