Rangel Will Give Up One Rent-Stabilized Apartment

I was out of town when this hit, so am coming to it a bit late. Based on what I’ve read, it seems as though Rangel was on thin ice for using one rent-stabilized for purposes other than a primary residence (it was his campaign office), but is OK on the other three because the mini-compound forms his primary residence. So today he has given up the campaign office, but is keeping the others.

Fair enough, its apparently all legal. But can someone explain to me why its legal? Why is a program that is designed to make more housing available allowing people to “live” in more than one apartment? This isn’t a question of Rangel’s right to live in three apartments, but one of a rent stabilization law that would allow any tenant to occupy more than one apartment.