Imagine a town with a number of wealthy homeowners, most of them old enough that their kids have grown up. Their municipality is already flush with cash. They already only need few schools for their kids and grandkids. They just want to pressure the less wealthy undesirables away, and use tax (dis)incentives to do that.
I understand the mid-term thinking.
Those extra water pipes and electric utilities, superfluous roads, excess lighting, and extra patrol units aren't going to maintain themselves in a lightening tax base. Same with the now-older schools built for their now-grown little kids when they moved in.
Long term, properties decrease as it is no longer a desirable area.