When I saw your question I had to go and look this song up because I have always sung 'off of' and assumed that was actually the lyrics. It does just sound better!
The Pet Shop Boys also sang it as ' off of', just as a bit of trivia
I was listening to this whilst driving home tonight (R2, Drivetime, a listener's request) and what a fabby track, I thought.... great song, much maligned singer... by the time I got home that tune was well and truly stuck in my head..... anyway.... I just add an extra syllable to the *off you* bit..... so in my head it sounds like, "oh-uff you"..... so I understand what you mean.