Barefoot when possible, during summer of course. Not if there are rocks, or thorns of course. In such case, I wear sandals.
Indoors, often barefoot, except put on slippers if going into attached garage. I avoid getting feet unnecessarily dirty.
Yes, inside the house
No, outside the house - too many stuff on the lawn, spiky weeds, ...the lovely feather kids poops, ....the tiny bantam poops, the big broody hens poops, I remove them, but knowing they were once there...bare foot no way Jose, no way!