I love ethnic food. I've thought a lot about why. Given the choice, I would usually rather eat something ethnic and cheap than something expensive and gourmet. I think it's because of the context, actually.
Ethnic minorities bring something important to our cultural experience.
Because, typically, minorities are oppressed, they often learn to make something beautiful out of what the general culture regards as humble or evidence of suffering. We are all outsiders at some level. Of course, I don't think this experience is completely conscious. Instead, we experience it in terms of heritage, tradition, memory, taste. The way memory gets attached to taste is fascinating and you can see this operating at deep collective and cultural levels in rituals of feasting around holidays and other special occasions.