Two words. Trail Running.Lol I'm not a runner and I never aspire to be, but I spend march to October in either flip flops or bare feet. By the time winter starts my feet are extremely calloused and that helps to prevent injuries, but I have cut the sole of my foot doing it and though the rest of u guys are laughing off glass in your foot to try to be tough, I'm honest enough to say that getting cut in the sole of your foot genuinely hurts.
Also I'm guessing that most barefoot runners or people who just go barefoot like me have experienced cuts on the soles of your feet. Yet you still claim that shoes injure people and barefoot people are perfectly healthy?
Also I'd like to point out that running on hard surfaces like asphalt, concrete, etc. hurts quite a bit and even though your feet may toughen up, cushioning protects the foot.
Another case is asphalt on a sunny day. BURNING HOT! I for one don't want to be without any foot wear when I'm walking down an asphalt road lol.
Going barefoot is awesome IMO, but don't promote it beyond reason.