How will it be a great deal? For 65 more years Chicago will be on the hook for paving and otherwise not using two lanes worth of road on a huge number of roads.

How will it be a great deal? For 65 more years Chicago will be on the hook for paving and otherwise not using two lanes worth of road on a huge number of roads. If self driving cars become incredible over the next 20 years, the city goes to all robot cabs and no private vehicles, etc. they will still have to keep those parking spaces or pay the parking vendor for them. For this year the city will be paying $20+ million and it's not getting even the ~24 million it would previously have gotten, so roughly a net -45 million for 2018 alone - and even not counting the money paid by the city the leasing company will have made back its entire purchase price by 2020, leaving 60+ years of pure profit. Chicago got taken so hard that it's now the canonical example of how not to do this kind of thing.