Some slang designations were always intended to be cruel or to mock: Polack, Bohunk, Kraut, Spic, Dago, Wop, Frog, Chink, Jap, Squarehead, and dozens of others were the result of hatred or scorn, whether caused by war, as were Hun, Kraut, Jap, Gook, and the like, or by the social strife that waves of immigration, competition, and poverty (and religious or racial differences too) have so often caused, which gave us Mick for the Irish, Wop and Dago for the Italian, and the term wetback for illegal immigrants from Mexico.
I'm just saying why offend when there are other, more appropriate words, one could use. That's all.