Imagine the alternative - people jockeying for the spots, or never moving their cars for fear of losing them. It may not be the most equitable solution to this problem, but I do not think there's anything inherently illegal going on.
You might want to post this question in the Nursing Home-Neglect forum. I'm not suggesting for a moment there's neglect here, but the attorneys who participate in that marketplace may have better information.
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