I can't believe I read this whole thread... that's what happens when you can't sleep!
The choice/born that way discussion has always fascinated me. Some things you can't change (born that way) obviously but I think that sometimes the "born that way" argument is used as an excuse for not wanting to make necessary changes in ones thinking or attitude.
I had a business for a little over 20 years and can honestly say that a clients sexual preference didn't concern me, I was more worried about if their check was going to bounce.