There is an odd appearance of courtesy/accepted habit here at work regarding the handicapped parking spots. Unlike the regular spots, which are filled up from closest-to-farthest as people arrive, the handicapped spots are filled up from farthest-to-closest (with one exception). From my point of view, it appears that there is some kind of unofficial expectation that, regardless of how handicapped a person is, the next person along may need the closer spot more, so it is best to leave it empty. Maybe I'm projecting altruism on strangers, but it does make me smile to think about it.
It does help that there are plenty of handicapped spots, with wide margins on either side of every space. And all of our parking is covered, so there is no rush for a particular area of the parking lot. With no artificial restriction of resources (handicapped spots), drivers can afford to be generous without losing anything from their own resource pool.