@IRFRANK,
I read some stories about the new Amazon plant in SC. The company supposedly agreed to spend $50M and create 400 jobs. The state and local governments promised new infrastructure (i.e. roads), real estate tax breaks for Amazon and the aforementioned "sales tax exception." I don't quite understand the details of the last concession.
These types of deals by governments hungry for development strike me as unhealthy. The numbers are spongy at best and there is too much opportunity for corruption.
The most egregious examples are the deals to lure or keep professional sports franchises where civic pride too often clouds sound planning.