A guy goes into the store and tells the clerk: "I'd like some Polish Sausage."

The clerk looks at him and says: "Are you Polish?"

The guy, clearly offended, says: "Well, yes I am. But let me ask you... if I had asked for Italian sausage would you ask me if I were Italian?
Or if I had asked for German sausage, would you ask me if I were German? Or if I had asked for a taco would you ask if I was Mexican? Huh? Would ya?"

The clerk says: "Well, no."

With deep self-righteous indignation, the guy says: "Well, all right then, why did you ask me if I'm Polish just because I ask for Polish sausage?"