The state house just passed a bill (senate had already done so) allowing for sales of alcohol to the general public and suites at TCF Bank Stadium, requiring "the sale or service of intoxicating liquor in a public portion consisting of at least one-third of the general seating of a stadium" or "at a location in the stadium that is convenient to the general public attending an intercollegiate football game at the stadium," or not at all.
All signs point to some sort of age-restricted beer garden in the stadium, but it will be interesting to see what comes out of it and if other schools follow suit. Estimating between $1.5m and $2m in additional revenue per year, I would imagine at a school that actually has fans that number would be higher