The overriding factor that many are missing is the role of fraternity life in student recruitment. I am sure that demlion and others will say bullcrap or worse, but this is a real issue if unspoken among administrators.
Bricks and mortar are no longer necessary. Therefore, what will bring students to campus sit their butt in an auditorium lecture? For some, not all, the idea of college life may include joining or partying at a fraternity. I am not saying this is right or wrong, but talk to a 17 year old kid and try to figure out what will get him to tell you what attracts him to go to a particular college. I have no idea what percentage, but an "active social life" with a fraternity will be important to some.
Remember, colleges are not just competing with other campuses, they are competing with online degree programs. Universities have to figure how to satisfy the desire for "active social life" either with or without fraternities and sororities. OR they may become dinosaurs. Liability issues will definitely disappear if the doors are closed.