> One company should not have bargaining power over an entire city, and they certainly should not get special economic treatment over others.

Depends on which city. NYC is an established city, with unique value proposition over the globe. I actually don't think losing Amazon would be a big problem for it overall, for certain region maybe, despite the drama. But that can't be said for any other city in US.

And you and I all know people get discounts when they buy in the same stuff for a larger amount. I see no difference in this case.