How do you know that only people from Fargo go to a NDSU game? Is there some tracking or evidence that demonstrates where people are from?
Even if you go one county away, lets say to Richland, Traill, or Barnes Counties, you enter the zone of declining population. These places are within easy commuting distance to Fargo, and the 10K to 18K that you are talking about is like what most Division 1 bball schools get at their games. Those schools don't just draw from the immediate town or metro area for the game, they draw from within 50 miles on weeknights, and from within the states' boundaries on weekend games. Football is a weekend games, unless you are a D-1A mid-major team playing on ESPN on a Tuesday, Wednesday, Thursday or Friday night.
So I don't necessarily believe they all come from Fargo, when NDSU is a statewide team, especially when you are still talking about 10K or more on a weekend which is comparable to D-1 bball.
What does Minneapolis have anything to do with NDSU? Its 250 or more miles away in the bordering state. Its the home of the 45K enrollment at U Minnesota.
A state as small as the size as ND has a lot of possibilities losing a number of things if its population decreases. 1.2% of its pop is ~7K. If it continues to drop like this, resources contract. The only other jurisdiction to be losing population is the District of Columbia, which isn't in any state. Many inner cities lose population. What that demonstrates is when population declines, tax base declines, services are cut. It can be a neverending cycle, because the resources are needed to help your state or city grow.
You should realize that I am talking long term if this trend continues. You may not see this right now, as it is relatively recent that ND has begun to decline in population. But it it goes on for a decade or two, the decline will began to make its affect known where you hadn't noticed it before.
Of course, it could be that all of a sudden ND begans to have net positive population growth. But even then, slight population growth sometimes might not be enough to sustain things the way they were before. But things could change. The 1990's saw ND with positive growth.
45k out of 322k 20-24 year olds. That leaves plenty for NDSU.
Trust me, both NDSU and UND get a lot of enrollment from Minneapolis.
In fact, UMN is trying to set up a game to play NDSU in the metrodome by 2007 because they know so many alumni live in Minneapolis that it will be a good draw.
Well, there goes your theories. Too bad.