And one of those groups (Ranchers?) commented that their playing changed when they decided to stand to play, and did away with the music stands and dots.

Flora mentioned dance cards. I never use them for 'general public' ceilidhs, though if I've worked out a programme in advance I might print out a list with a few reminder of dances I use less often. And glance at the music stand when I go back to the stage to talk to the band.
But a dance club is different. I have a much bigger list of dances to work from. So I take cards. But I will have practised enough at home with cds to pretty much not use them use the music is playing. Having reminded myself in the walk-through (mustn't get the walk-through wrong or the wrong patterns are firmly imprinted in dancers brain - they take no notice of corrections and apologies).
On one occassion I suddenly noticed that there was a multiple of 5 couples, (not often the case), found the tape, walked and called Levi Jackson, and after the dance noticed that the 'talisman' card in my hand was for some other dance (the one that was on my list).