I'm a little obsessive about wearing suitable riding gear--you'll very rarely catch me out for a quick spin without a jacket, gloves and full face helmet. Sure it takes a little more time to suit up and I'll have a few more things to carry or stow when I get to my destination, but it's much better than the alternative. Even a minor spill can result in some painful road rash. And who really wants all the random things that hit you while riding (from bugs to small rocks) bashing you in the knuckles, eye or arm and tarnishing an otherwise delightful ride.
For some local jaunts this weekend, I traded my armoured jacket for a leather one--much more stylish and less bulky for walking around town. And it was the perfect temperature for it--not too hot, not too cold--gotta enjoy these lovely fall days while we can.