Nothing suggests that the company operating the jurisdiction would be the sole, or even a significant, employer.

Given that cities often are responsible for zoning, and the company is taking on the role of city governance, a company could do a lot to ensure its the only employer in town. Obviously this depends on the particulars of the bill, but it doesn't seem far fetched that companies could put some serious disincentives towards other companies forming.

Ok, strike "fired" from the list. Maybe. It's still a concentration of power and the same rules apply. Attractive at first, but then it goes sour when the people with concentrated power start using it for their own ends.