Some people don't realize they're doing it or don't realize that it hurts some people, and would stop or try to if they did. If you try to set an example yourself and politely correct others, some people WILL make an effort to stop saying it. The fact that it is so ingrained in our society that some gay people will say it without even realizing what they're saying is kind of sad. "Be who you are and say what you feel-those who mind don't matter and those that matter don't mind."
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