It is a licensing issue - but it could also be a facilities issue. I'd have to check the laws (new, old, in between), but IIRC you have to have areas set aside for service of "intoxicating" beverages (low point beer is sold under the myth that it is "non intoxicating") that restrict access to minors ("21 and over beyond allowed beyond this point"). If the ratio of sales gets skewed, the location then becomes a bar with restricted ages throughout. I have never researched how that works in a large venue...but they are issues to consider. Also, there is the issue of dram shop exposure. Low point is considered usually less of a risk (whether it is or not).
Not that it really matters. It appears the University doesn't have a high-point license of any kind. Sodexo does. Presumably the other vendors have individual licenses also (OTC or low-point licenses are not listed on ABLE, obviously):
https://www.ok.gov/able/documents/CAT.pdf
https://www.ok.gov/able/Monthly__Reports/index.html
Not that it really matters. It appears the University doesn't have a high-point license of any kind. Sodexo does. Presumably the other vendors have individual licenses also (OTC or low-point licenses are not listed on ABLE, obviously):
https://www.ok.gov/able/documents/CAT.pdf
https://www.ok.gov/able/Monthly__Reports/index.html