Another similar topic is the "moving walkways" at airports that give you a big speed boost if you actually walk on them, but are slower than walking if you just

Another similar topic is the "moving walkways" at airports that give you a big speed boost if you actually walk on them, but are slower than walking if you just stand on them. There seems to always be a group of people standing side-by-side on those just chatting away, making it so others can't walk past them. Those are wide enough to stand on one side and let others pass, but they rarely do.