Robert Rosenberger calls attention to urban design choices meant to deter the homeless:
An example of a pervasive homeless deterrence technology is benches designed to discourage sleeping. These include benches with vertical slats between each seat, individual bucket seats, large armrests between seats, and wall railings which enable leaning but not sitting or lying, among many other designs. There are even benches made to be slightly uncomfortable in order to dissuade people from sitting too long.
Sadly, such designs are particularly common in subway, bus stops, and parks that present the homeless with the prospect of a safely public place to sleep.
When thinking about this landscape of homeless deterrence technologies like the benches and still-ubiquitous spikes, it is important to consider the role of laws against loitering. For many cities, loitering laws have the effect of enabling law enforcement to arrest the homeless simply for being around. Such regulations target things like sleeping in public, panhandling, or even outdoor charity food service. This further complicates the relation of the homeless to this public landscape. Why do you think the homeless so often choose bus stops in particular as a place to sleep? One reason is surely that it affords a kind of plausible deniability: I was just waiting for the bus.
The Dish 