First of all, married scholarship athletes qualify by NCAA to get more money in stipends from the university. BYU is at the top because of all the married student-athletes. Guess who the next school is after BYU? It's Utah. USC was at the bottom of the list because of their scholarships that were taken away.
It's still illegal (from NCAA) for schools to just pay students more money to attend their school. None of BYU's athletic money is from tithing. BYU Athletics receive $0 from tithing. It pays completely for itself and everything in it.