I don't understand what your real point is. You can decorate the entire stage, but what does that really have to do with the band or DJ?
Are you suggesting that if you didn't have a front board people would stop hiring you to DJ? If so, you've misidentified your true business.
I have gigs where all I do is the decor which might also include building or providing the booth for some other DJ. It's a different job - neither one depends on the other. There's no mutual exclusion - a DJ can have a front board and still be mediocre.