Add Stanford to the list as well. They used to not make any commitment until the player already had a high enough ACT/SAT score but apparently having lost out on a number of recruits, they modified the practice to make offers but contingent on meeting their minimum score thresholds. Sure they may still lose out to other schools who do not have similar contingencies, but they need to be sure the athletes they recruit can cut it with a student body of exceptionally bright students.
There have been other threads here that note how it is now all about ACT/SAT scores for the academic schools. Right or not, GPA inflation has occurred at many schools in response to the ever increasing GPA requirements at many colleges and universities. The University of California system is insane with most schools in the system now reporting average GPAs for incoming freshman over 4.0. So many of the coaches and admissions officers at academic schools have wised up and are emphasizing the ACT and SAT as the driver for accepting recruits. The demands on student athletes are well-documented. The worse thing they can do is bring in recruits who cannot cut it academically and then both the student and school lose out. The ACT/SAT tests have their critics, but they give a more clear indication of what a student's potential for success is than a possibly inflated GPA does.