It's simple, really. Universities are rated by personnel at other universities. So, if you want to be ranked in the top 10 MBA schools, for example, you have to impress deans, presidents, and etc. of other schools... all of whom are extreme leftists. UNC-Chapel Hole has probably already moved up a couple of notches on the various lists.
I had a prof who called it the "Lefter than Thou" approach.