I was having a heated debate with a friend a few weeks ago about gays and marriage. He had been in the Navy years before there was DADT. There were gays in the service but nobody cared then, hell he didn't care so he was a tolerant guy. His problem was gays being out in the open where they were "shoving it in our faces." with all the talk of same sex marriage and rights. He wasn't feeling very tolerant of them now. Why should they have the right to marry? This is where we parted company in the debate.
Since then I have been giving this point of view a great deal of thought. It reminded me of the old convenient excuse "I don't mind black people as long as they don't live next door." It's easy to be tolerant when you don't have to deal with your discomfort every time you step outside and the black neighbor waves hello to you.
Allowing gays to be open means having to confront ones own bias, translation: you're not ready, able or brave enough to actually defend their right to be who they are. When gays come out and demand true equally it challenges the status quo and that may force you to chose sides in the debate when it's so much easier to believe they don't exist to ease your peace of mind. If only they had kept their place so you could continue to view homosexuality as some dark social secret. When they're in the closet it means you don't have to worry about changing your mind because they aren't "shoving it in your face."