I have hamstrings that didn't grow right during puberty and basically that means i don't have a rest position when standing. I'm always exerting energy when standing even though I can walk just fine, and eventually it hurts and I collapse. The fact that people can just stand and wait for something is entirely unrelatable to me.
Not really, you need that forward motion. Walking in circles is a thing, but that still takes energy. Really I just sit whenever I can.