I agree that everyone is paying for them via the tax incentives. But I think the media portrayal is often incorrect about who benefits. The benefits of tax-exempt bonds are split between the municipality issuing them and the high-income individuals buying them. But most of the gain is captured by the municipality (because the high-income people would be getting a lot more interest in a taxable investment so the municipality would have to pay a lot more interest to raise money if they had to compete with those investments).
If players have a union and collectively bargain, and the owners collectively bargain, then the fans/cities should also collectively bargain. Create a union of the cities that host the leagues, and have them bargain for rules such as no taxpayer subsidizing of stadiums.
Federal Government should not be allowed to tell cities how to spend their money, but something needs to be done what devinhelton said. Look up Atlanta about their stadium deals for the Falcons and Braves. The City Council basically ignored the citizens completely and went ahead to spend millions to replace 2 stadiums that really wasn't that old to begin with.
Did the city council get re-elected when they went against citizens?
Im not sure. I remember reading an article about it awhile back and wondered if they would get re-elected, though I cannot find that article at the moment. I believe it was to approve additional funds for the Braves new stadium. If I remember right, they kept anybody who was against the deal from speaking about it at the meeting. There was a big scene and they went ahead and voted for the additional funding.
The Braves aren't in Atlanta/Fulton anymore because the city wasn't willing to pay for a new city. They are in Cobb County - a suburb of Atlanta.
Cities do have a "union", it's called the city government. Fans (aka people) bargain by electing people that agree with them. So far fans (aka people) are electing people who think the cost/benefit of paying for stadiums is a net positive. If so many cities wind up taking a loss on the matter then I suppose things will change.