Constant movement is the modus operandi of anyone consigned to life on the streets.
The structure of the men's bathroom is meant to discourage it as well. Maybe in a totalitarian regime, there wouldn't be any door on the stall at all. As usual, though, these rather ethereal democratic considerations become inconsequential when their ballasts give way under the weight of immediate, practical reality. All the missing half of the door means when you're on the business side of it is that there's a continuous stream of people looking down at you with eager eyes, to see if the toilet is truly occupied. There's a certain, unmistakable stench that lingers after smack has been mainlined.