The Sacramento Bee recently pointed out an economic benefit from professional franchises that you don't see much press about--players on VISITING teams have to pay local and state income taxes.
The Bee article explains:
Professional athletes are required to pay income taxes in every state and city that levies them where they earned a salary during away games. That means Kings and River Cats players must file tax returns in dozens of states and several cities. In some jurisdictions, that includes practices, as well.
Each state determines taxable service performed, also known a "duty day." The nonresident income tax, which is dubbed the "jock tax," surfaced in the 1990s as a way for states to tap into the soaring paychecks of visiting professional athletes, said Ryan Losi, the executive vice president of Piascik & Associates, an accounting and financial services firm in Virginia that works with professional athletes.
Losi said many believe "jock tax" enforcement began when California taxed Michael Jordan when the Chicago Bulls beat the Los Angeles Lakers in the 1991 NBA Finals.
Today, taxes generated in California from visiting athletes bring in an estimated $100 million each year, according to the state tax board.
In other words--by having NBA, MLB and NFL franchises, the state of Wisconsin can collect taxes from a significant number of NBA, NFL and MLB players (particularly in the case of the NBA, where every team has at least a home-and-home series with every other team--the state can thus collect taxes from every virtually player in the league).
The taxes collected are probably not anything close to what California (with its multiple baseball, basketball, and hockey teams) generates, but given that we're still arguing over whether Miller Park was worth it--and are almost certainly going to go through the same debate in the near future about renovating/replacing the Bradley Center, lest we lose the Bucks--this is something to keep in mind.