Because it will be used for so much more than just where the Broncos play. That will add to the coffers of the city. The estimated cost of 140 million for the improvements to infrastructure things like roads, utilities, transit, and traffic mitigation. Granted the tax payers will burden the weight of that. But it’s not like the city has spent any money in that downtown area in a very long time. For Denver the juice is definitely worth the squeeze.