I think in a way, it is fair to use the "what else is there to do" up there. I know there's more to do than ever before, as JSF said. Many people root for where they're from, and the schools up there are the biggest shows in town.
They don't have major conference schools in every direction around them, and they don't have an NBA/NFL/NHL etc team right up the road in every direction. Yes, they do have Minneapolis close by, but it's nothing like way it is here in Ohio. That has to play a part in their support.
Isn't that balanced by the fact the towns aren't very big, whereas the big cities have a lot of competing options, but also a lot more people?
Could be - but I think being THE team in a given market/region has a lot to do with it. Look at OSU fans. They'll drop $100+ to watch football in numbers over 108,000 every Saturday. But in Basketball, selling out 19,000 seats at $30-$40 per ticket is an absolute chore.