1 reason: recruiting
kids want to play for winners. Over the years a lot of high-profile athletes have come to BYU out of loyalty or because mom/grandma made them, but to get over the top you also need those special athletes that grow up wanting to play for you because the program is a proven winner.
If I were in Utah I'd probably think different with my Ute neighbors, co-workers, family, home-teaching companion, etc rubbing it in my face. I haven't met a real-live dedicated ute fan since I moved out of Utah 11 years ago.