Had to look at that last one a couple of times to be sure it was not me. I have boots like that for working on the ranch, and several work benches with butcher block surfaces.
Figured out that was wood flooring, not enough laces in the boots and threads were too far out of focus, so it is not me. Software that came with my camera allows me to crop my feet out most of the time anyway. Now that I know it is a thing, I will have to leave my feet in at least once.