We all have prejudices against each other, and these things come out. They're revealed by the person's accent and other people's responses to your accent. In fact, there's a quote by George Bernard Shaw in the preface to Pygmalion: It's impossible for an Englishman to open his mouth without making some other Englishman hate or despise him. We all judge each other on our accents, and different groups sort of will hate each other for different reasons.