Sorcha: I don't think the fact that GSA and BSA receive funds from United Fund or United Way would qualify them as having received public funds. I guess it depends upon your definition of "public." (Sort of like what one's deifinition of "is" is.)To me, public funds means tax monies. United Funds receive voluntary donations. It should be up to the United Funds to police their own distribution policies.
Denying private nonprofit organizations the benefits of nonprofit status because the government does not approve of the organization's membership requirements might be a possibility though. I would think that sexual preference might have to be recognized as a disability though, for the government to get involved. I doubt that the Gay and Lesbian communities would approve of that.
DougR