You are right. If you are a private organization (church, club, or whatever) you are free to serve who you want within that private organization. But once you are serving the public you cannot discriminate.
Look guys, my point has nothing to do with whether a business should be required to serve the public. Of course they should. But serving someone breakfast or selling them goods and services (clothing, shoes, insurance policies) is not the same thing as the example I cited above. Those of us who are in business sell and provide services to people every day without having an inkling of their sexual preference. And even if we did know their preference, it wouldn't matter one way or the other to most of us.
It's an entirely different ballgame, however, when a business owner feels he is being compelled to actually become a participant in something that goes against his religious convictions. Folks who believe that same sex marriage is contrary to their principals should – in my opinion – not be forced or coerced into doing something that could be justifiably be seen as an implicit celebration of that event.
Anyhow, I strongly believe this board should be limited to discussions of basketball in general, and Sooner basketball in particular. I apologize for letting myself be drawn into this argument. I am no activist regarding this issue, so I am now respectfully bowing out of the discussion.