Good points Five1, but if we look at it like that, I would say that wearing a helmet can help in maintaining control as well.
If I'm riding around without a helmet and bugs, pebble and other debris is striking me in the face, I may be more likely to constantly wipe my face off or protect my face, which means I'm constantly taking my hands off the controls.
Also, I don't know about anyone else, but there have been occasions where I have been riding and chunks of paint were taken off my helmet from debris. God only knows what that would have done to my head if I wasn't wearing it.
Yes they are different, but both with a common themes: Safety.
I like to feel the wind in my hair to (or lack of, as I am going bald), but that can be solved by buying a helmet with good airflo, which my X-11 does exceptionally well
Now, I am curious to why certain states require them and others don't. Is it because the number of deaths involving riders with no helmets?!?