It really is so easy to decide, for most people, that surviving a fall or impact versus the feeling of wind blowing through your hair is a, pardon the pun, no brainer. Not wearing a helmet also can put one's hearing at risk to with freeway speed wind blowing into the ears I believe it can damage hearing.
Those who decry oppressive helmet laws usually argue that it's their choice and it's only their business but I wonder how many who are injured or killed while not wearing a helmet wind up suing someone for the injuries, costing insurance companies, corportations, or taxpayers money for the extra treament required by the more extensive injuries, and the inevitable law suit against the driver involved is an entirely different issue....