I heard a story on NPR today that mentioned a guy who dressed as Superman on an airplane (because he felt like it). That reminded me of The Brothers Four song Superman. The song starts out with a ‘Swedish’ guy (‘so we won’t offend anyone’) who has a towel concession for drying off wetbacks. Yikes! They got away with that?
Then I thought of another song, Jump Jim Crow by Michelle Shocked. According to the liner notes (going by memory here), it is a tribute to minstrelsy (and is based on a 19th Century song) that aims to point out the stupidity of racism. Only without knowing the intention, it might be pretty offensive.