I think everyone automatically uses stereotypes up to some degree. For example, if someone is telling a story about his friend (unknown to you) in a far away country, the first thing that comes to your mind is the stereotype you know about the people in that country. After that first thought you may correct yourself (no, Jack, that's a stereotype, cut it out!) or your first imagination of the friend may change because you're provided with extra info about him, but that very first thought is still your very first thought.