This isn't a big deal.

1) Who owns the parking lots in question? If they charged what I would assume to be a "decent" amount of money to park and allow tailgating, they aren't they doing anything to clean the mess up?

2) Did the people who wrote/covered this story stumble upon this mess before they had a chance to clean anything up?

3) What about other 70% of the city that looks like shit? Who are they going to blame for that?

A few messy parking lots left by some drunken professional sports fans doesn't really register in the whole scheme of things if you think about it.