Agree with cRusty.
Not a big Cowboys fan, but Jerry Jones only "made" Arlington pay for the infrastructure around AT&T stadium, the roads and such, he didn't make them pay for the stadium itself.
I could be mistaken, but I think that deal has worked out well for the City of Arlington relative to the number of large events AT&T Stadium now attracts.
San Diego only dropped below 60K a game this year after years of really not doing anything. Otherwise they've averaged 65K a game for as far back as I care to look. Admittedly their %'s relative to number of seats available is on the lower side in the NFL, but the Murph has always been too big for that market and that demographic. Plus you'd have to say their attendance may have been impacted by the fact that a lot of seats at the Murph are crap, as it was originally a multi-purpose stadium. There's no indication that they couldn't build and fill a 65K seat dedicated football stadium at 90% plus of capacity on a regular basis in San Diego.
You can build a decent stadium, even in urban California and not need to spend a billion dollars.