Interesting topic, but also highly pertinent I believe. I do not consciously make disparaging remarks regarding gay/not gay. I consider myself bisexual and enjoy both men and women.
Perhaps, for some (used to be the case for me) they still feel some shame over CDing. Therefore, this may result in a small % thinking that making rude comments over gay people, somehow proves they are still a masculine individual. Well I maybe incorrect, but that is my experience.