Often they don't pay high taxes nor do they employ large numbers of people. Most of the money made by leeching of public power infrastructure and cheap electricity and export the profits to somewhere else. They are building and selling a non tangible good i.e where do you tax it?
Their is also noise pollution concerns which can destroy communities near by and water usage concerns. These plants drain aquaifers.
I just think you haven't substantially thought about the effect these have on the actual people living nearby. AI being .000001cent cheaper just doesnt help people that much