My dad was saying something similar a while ago when somebody mentioned the packer wanting to move to Milwaukee. Not only is it the home team, but it is the only publicly owned team. Whenever they want to expand tou whatever, they sell stock to the fans to get the extra money to do so. I'm sure the city helps but the amount of tourist money the city makes during football season kind of balances out.
I dont know all the details or even if any of that is completely true, but that's what I've heard.