This isn't additional revenue. On average athletes, prob especially football, are taking a spot that a higher ACT/SAT student could have had and such student would be paying tuition. The AD is just making up for tuition that would've been recieved. This however doesn't compensate for the student who was qualified but didn't get admitted. A lot of universities have athletic scholarship positions endowed so the tuition payments aren't in such cases coming from new TV etc. revenue. If athletes are paid then they will need to pay taxes and pay there own tuition.