There is no high attendance football program in a large (top 20) metro area.
I think it largely goes to the idea that college football cannot possibly dominate culture in such a place.
Those of you who are more familiar with West Texas can probably school me about the HS football culture there. But IMHO the reason that HS football is such a big thing in these small towns is that
the entire town gets involved in it. And why does the entire town get involved? Because the entire town gets involved--there will literally be nothing else to do on Friday nights.
I think this is true of most "college towns" for football. I think of Lafayette. Not West Lafayette, where Purdue is located, but the city of Lafayette, across the river. My guess is that retail businesses, hotels, restaurants, etc ALL know when Purdue home games are scheduled. Because a Purdue home game--relative to normal economic activity in Lafayette--dominates on those days/weekends. And... We suck!
But Lafayette has a population of 70,000. If Purdue has an attendance of 45,000, and 2/3 of them travel into town for the game... That's half again the population of Lafayette.
That means that a home football game in West Lafayette and Lafayette is a major event. And thus, people treat it like a major event.
Compare that to USC. USC is in the Los Angeles-Long Beach-Anaheim MSA, home to 12.8M people. Even if you filled the Coliseum with 100,000 fans, would the city notice? Nope. Not one bit. Most people around here have no clue whether USC or UCLA has a home game on any given weekend, because unless you're literally on either campus, it has no effect on your life.
So I think it's hard for metropolitan schools to build that culture, that on home football Saturdays, the
only thing going on in the town is football, so you'd better get on board with it.