More concern with pro-teams coupled with the high school football obsession in the south/Midwest that leads to more interest in following college careers. Also, there is a more transient population on the east and west coasts, so you don't have the huge alumni communities around the area of their college, and lastly, a lot more of the schools on the east and west coast tend to be of higher academic caliber, thus they don't have the same recruiting reach to field "dynastic" teams year after year
This is single handedly killing us at GT. Too many of our alums are spread out all over the country, we have limited majors, no liberal arts curiculum or majors, a board of Regents who refuses to add curriculum/majors to make it more "athlete" friendly, and what jock wants to take calculus.