Non-traditional Organizations

I have been talking to some of my sorors and other members of BGLOs on predominantly white campuses and have found that many (not all, so don't send angry letters about how your campus is different) campuses consider BGLOs "nontraditional organizations" and are either barred from or strongly encouraged not to participate in Pan organizations. This is astounding to me due to the fact that many of our organizations were founded (way) before other GLOs. Does anyone have some information on this topic?