That's like asking why College Gameday still lets Corso blabble on even after his stroke.
You may not like Vitale, but clearly enough people have over the years to keep him tenured. I don't care for Vitale or Corso personally, but it is undeniable that they have brought a lot of excitement, tradition, and familiarity that college athletics needs in order to compete for views against professional sports.
If you don't appreciate the whole "wearing emotions on your sleeve", being corny but passionate, then...well...