I know before I looked up the lyrics to At the End of the Day, I always had trouble with the lines,
"While we're earning our daily bread
She's the one with her hands in the butter
You must send the slut away
Or we're all gonna end in the gutter!"
I think heard something to the effect of, "She's the one with her hand in the garter!" for the first one, which made no sense, and the second lines wasn't intelligible at all for me; I think I mostly sang it by syllables rather than words.
Also, for the, "You play a virgin in the light, But need no urgin' in the night!" I always thought that it was, "But meet no urchin in the night!" which only succeeded in producing strange mental images of either Gavroche or sea creatures at dusk near the factory.