You have the obvious bigots, who proudly wear their bigotry on their sleeves, and who have enough self-awareness to know they're bigots.
But then, you have those people who, as far as they're concerned, aren't bigots, at all. They may be nice people. Consciously, they may genuinely believe in say, gender equality. But, they are subconsciously bigoted. They'll have a bigoted reaction towards a certain kind of people, but not be able to explain it. Or, they'll be a little aware that they may sound bigoted, but make all sorts of rationalization to explain why their reaction is anything but bigotry.
Repeated exposure to stereotypes, combined with a weak will, minimal imagination and ability to think for oneself, all play a role in subconscious bigotry. They frequently see people of a certain ethnicity in fiction play a certain kind of role, and whenever they see someone of said ethnicity in a non-stereotypical role, particularly one that is more flattering and empowering than the role(s) said race habitually plays, to these people, it can never seem right. They're too closed-minded to be fascinated by something so refreshing.
Has anyone here ever been guilty of unintentional bigotry? Because I'm ashamed to say that sometimes, I have. But fortunately, I always think it through, always get over it. I'm pretty open-minded for the most part. I remember when I saw the Spawn movie back in the late nighties. I was a pre-teen then. I was used to characters like Spawn being white, so when I saw that he was black, I actually liked it. It was refreshing. Still, I can't always escape society's bad influence, but it always fade away, fortunately.