People want to spar without protective gear all the time. I warn them that it's going to hurt, and they all say the same thing, that I won't even get a hit in. Just because I'm not kicking you between the legs doesn't mean I'm not going to hurt you. The only time not wearing protective gear is acceptable is during competition, and even then, head gear and mouth guards are advisable. Don't blame me if you're not wearing your helmet and get staples in your head.