For me, a dancer is part of an artist's entertainment - 'backup dancer' isn't even in my vocabulary.
If you look at some shows that have an ugly feel to them, or a nihilistic sort of feel to them, you'll usually find a group of cynical, unhappy, miserable people behind the production. If you see a show that's rather boring, or a cookie-cutter factory show, you'll usually find some pretty uninterest

