Well, my question is whether you are including the NPHC fraternity Omega Psi Phi in this...
From
http://www.omegapsiphifraternity.org/mofaq.asp
Q. What is the position of the Fraternity for Non-Christians who make application to become members of Omega Psi Phi?
A. Omega does not have an open admissions policy. It is a privilege to become a member of Omega Psi Phi and the Brotherhood is based on men who espouse Christian education and beliefs.