Perhaps the goal is to purchase the homes, which are too low-valued for the homeowner to get a fair price, and turn them over to commercial development - i.e. bulldoze them - for new office space, for example. Then the tax base goes up when businesses move in. Perhaps new high-rises as well so that they have higher-density habitation. Again, the tax base could go up.

It's pure speculation on my part, but it's the only rational reason I can find.