The selling off of parking is going to haunt Chicago forever. They didn't just do it too cheaply, they did it stupidly.
When I lived in Providence they did a similar thing, except the Mayor was smart enough to include a "we can cancel this at any time for any reason" provision in the contract, and they did cancel it pretty quickly. It turns out the enforcement of parking regulations has a broader public policy purpose than simply raising money! Shocker!
