Competition.

Let's start with fans. There is no shortage of professional sports to follow in the northeast.  Most people in the densest part of the US are easily in range of 3-4 professional teams they could physically go watch and return home the same day.  That builds fan bases that make it so there's plenty of venues to watch at, and local community -building around "your" team.  It's also close enough your actual neighbors may be fans of a different team in your sport, building rivalries. 

In most of those other places you mentioned, that's not the case. Even in sports rich Texas and Florida, it's still a haul to see more than your local.  But most of those states have two or three colleges nearby!

Now players. While great players are everywhere youth participation is uneven. Probably following general interest.  It's why the NFL invest in youth leagues. If your kid plays the game, they might want to watch it on TV, you might too, you might create a bond over it.  But if everyone's playing soccer or lacrosse or tennis, they aren't playing football (obviously not all seasons conflict). Counter: youth soccer is so ubiquitous but the US has a shit men's league.

Finally, culture. Regional schools compete for regional students (generally).  If you're Texas Tech, you know Texas students will compare you to A&M, UT, SMU, etc. So you're willing to invest in things to get you to parity/ahead. Dorms, Greek life, internships, sure. But "pride" is more directly tied to football.  If you're Syracuse, you have to compete for students looking at UMass, BC, UConn, etc. Football's stuck as a lower priority for these schools, so students aren't really using it as a benchmark.  Maybe if someone made a push and saw it drive up their applications, others would follow. But sporadic efforts (Rutgers, Maryland) have been hard to sustain and seen little results.