Lol no, a professional sports team is of little "joint benefit to society", at least not of the kind that seriously concerns the government. You may as well argue that the government should be subsidizing new Marvel movies, or Call of Duty, because those are popular forms of entertainment too.

> Also the only way to stop these gifts to private companies is likely with a new federal law banning them. It is simple game theory. These businesses will go where the profit is. Any city or state that refuses pay will lose out until every city or state refuses to pay. The best way to force that is with a federal ban.

No. You can just...refuse to subsidize them. Seems to be working fine for Seattle, where IIRC the renovated stadium for their new NHL team was privately funded.

And if they do go somewhere else, what's the downside? Seattle lost its NBA team a while back, which was a bummer for basketball fans, obviously, but otherwise what was the harm to the city or region?

Plenty of high prestige world cities like Tokyo or London or Paris aren't known for their pro sports teams. They seem to suffer little for it.

For a while, the Olympics were able to basically threaten their way into huge subsidies from even developed countries, but this seems to have mostly gone away now, as everyone collectively woke up from the delusion that the Olympics were a major economic boon worth investing in. Sports team stadiums could easily go the same way.

edit:

Okay, obviously I should've picked different world cities as examples, but even taking those: Tokyo's pro sports teams don't have anywhere close to the foreign popularity that London's EPL teams do. Does that seem to hurt it?