It seems that more and more thats what people want. I get calls to DJ and they always ask "do you do line dances" Answer is yes but I don't run around the stage I just play them.
I've had a nice job at a CC every year for the 4th. Just DJ by the pool. They didn't want any keyboard or vocals. Last year they had a new mgr. When I showed up he asked if I could do kids games and give away prizes. Luckily it was about to rain so I had to play inside and got spared from being the kids clown act. Next year I think I'll turn that job down even though its is big money.
I draw the line too but theres less and less call for just music at parties. Still hoping for that elusive restaurant job where I can just play and sing.