It costs the city a pile of money to host the superbowl, it is far from a profit making deal. Extra police and fire overtime, traffic control, trash pickup and all the other costs. All that in exchange for a 1 week increase in hotel and restaurant taxes and a few extra tips for the bartenders. All the big hotels are based elsewhere so that profit goes out of town and some of you might recall that the NFL brought in a limo service from New York because they were used to using them, rather than a local company.
Also, as I reacall they had to lower the field and add extra seats to get up to some minimum number the NFL required. So if a new place is built with all those extra seats they will never fill it on normal weeks.
The whole thing is a bad deal all around. Not one single city that has been bullied into building a new staduim has been able to turn a profit. Petco is still costing $20million a year right out of the city budget.