Many places with the only show in town do not sell out and they have been nothing but mediocre.
I don't disagree at all; winning/competent marketing are important anywhere. But those standards are definitely raised when alternatives are present. Minnesota is such a unique B1G school in that regard. The only school that really comes close is Maryland with DC. Pretty much every other school is synonymous with its town. You hear West Lafayette, Ann Arbor, Madison, East Lansing, etc. and the mind instantly goes to Purdue, Michigan, Wisconsin, MSU. That doesn't happen with Minneapolis (and never will).
Apart from winning, or just making tickets dirt cheap, I don't think there's much that can be done to put butts in seats for the long term. We saw the hype and corresponding attendance to start the season two years ago. Student tickets sold out for the first time in a long time. We sadly know how the rest of that season went down. On the price side, we see success with the opener at every football game (free student tickets), and one of the basketball games last year (I believe it was Utah).
I'm kind of going on a tangent, I know the point of this thread wasn't to directly compare Purdue and Nebraska to the Gophers. I just think it's an interesting conversation to have.