It's a free market approach. The alternative is that the government collects money everywhere equally and then go and invest/pump money into these area. If the

It's a free market approach. The alternative is that the government collects money everywhere equally and then go and invest/pump money into these area. If the area is tax negative (requires more government money than it brings in), then might as well give it tax breaks; if that economic activity can break it off the cycle. The very fact that some of these places exist for a long time; means that it's not worth it to invest in them even with the tax breaks.