You are missing basically the whole point of my comment. You don't have to enter a stadium or even pay a cent to a sports team to get utility from it. You can watch a game on free over-the-air TV or you can enjoy the communal aspects that other comments in this thread have mentioned. The business is generating positive externalities and therefore it might be appropriate to subsidize it.

Also, you might not want your tax dollars going to support professional sports, but many people do. That was my other point. We live in a democracy and the people generally are in favor of sports. The exact entertainment value it generates is debatable, but it is enough that these deals can be justified without requiring them to turn a profit. That was the only way I was comparing parks and stadiums. They don't need to be profitable to be a good use of money.