You might as well ask why someone doesn't like cheese, to be honest. People are born different, raised different, and think different, and that all has an impact on how someone is going to react to your crossdressing. It isn't like its as simple as, "oh, if she knew all along, she'd have accepted it for sure." Some people can tolerate it, some people love it, some people hate it, some people couldn't care less. Everyone is different, just like everyone else.
