Good point, my university has several frats/sororities attached to the marching band which do a lot of great service stuff for the department and local music groups. They also function as effective mutual aid groups when it comes to academic or music stuff, and would be a really great structure to emulate in socialist groups/communities. Problematic frats are allowed to continue, especially at more expensive universities, because they can connect students to influential alumni/opportunities, making them more "successful", and able to donate enormous sums of money to the university.