Honestly why would you not wear one
The helmet makes the ride more comfortable
Keeps bugs, stones, sand, exhast,etc from hitting your mug
Protects your eyes
Keeps your head warm-allowing us in wisconsin to get a few more weeks in (it is funny the crap people wear on thier heads-multiple bandanna, fur hats, leather beanies, watch caps- all not nearly as effective as a helmet in retaining warmth)
Keeps the sun off your head in warm weather.
I don't dress for the crash- I dress for the ride, not sitting in a bar or at a festival!