This is kind of like how really high end restaurants sometimes don't get as good of a review as just a decent restaurant. It is because if people are paying $100 for a stake, they want to taste a big difference than a $20 outback stake.
I have been to 2 private univ and 2 in state univ and I have found the in state kids really didn't care all that much about grades. BYU was by far the kids cared and worked the hardest, even compared to grad school