If I was a city boss, I wouldn't contribute to a stadium for some team. I'd let them go to some city that will.
But it wouldn't have to do with checking their balance sheet and making some decision about how much money they should make. Cities and states give incentives all the time to bring industry to their state (jobs and economic development, spurring the economy), and the whole point is that the company will be making money.
I figure the reconfiguration of roads, parking, etc. is enough of a helping hand.