These big first weekend blockbuster games are now a permanent part of the college football system, as the sport has the day to itself with the NFL not starting until the next week. And the off-campus part of it is pretty simple if you follow the money. Students don't get in free and boosters can be hit up for more $$ over and above their season tickets and booster club platinum level donations, plus they can sell it to a corporate sponsor (i.e. the Chick Fil A Kickoff Classic) which they cannot do on campus.
We were part of this last year, with a nationally televized game vs a Big 10 team. We will be again in future years.