I saw one guy walking barefoot at George Mason University once. I don't know what GMU's rules say about that though.
You might think they fit you well, but here's the thing, take them off and look at your foot. Notice how the toes have all been bent inwards and some are twisted so the toenail points outward instead of up? That's because a lifetime of wearing shoes has moulded your foot into a shoe shape, if your feet weren't forced into shoes from an incredibly early age they would be shaped like the ones I posted on page six and wearing shoes would be viciously uncomfortable for you. Much more uncomfortable than for someone like me who has simply given them up up. Like I said - they aren't designed to the human foot at all. If they are comfortable it is just because you are used to it. Lip plates are comfortable if you have been wearing them all your life. Have a look at this set of quotes from The Unfashionable Human Body.