"Just a few observations sid:
1. i assume you do not hike in cold wet conditions without shoes
2. How do you handle poison ivy/oak/sumac, razor weed, or other poisonous plants?
3. Are your feet huge and hairy now? like a hobbit?"
1. You assume wrong. The coldest I have hiked barefoot was in the low 40s, high 30s. I have hiked barefoot in cold and wet conditions on several occasions. My feet get cold, but it's not cold enough to give me frostbite. I've never hiked barefoot in snow, however.
2. Fortunately, I am not allergic to poison oak, so it does't effect me even if I do step on it. I have yet to step on a poisonous plant, however. Obviously, when you hike barefoot, you are much more careful what you step on. By being cautious and watching my step, I can avoid poisonous plants.
3. I suppose they are pretty big, but I don't believe going barefoot has caused my feet to grow more hair on them. As a child, I ran around barefoot most of the time, so my feet were already pretty big. They did get a little bigger from building up my feet muscles though.