I agree to an extent with the Dont Judge Book By Its Cover, but i dont think that was what they were doing. It was that silly thrust she did to them after she revealed her age what made them role their eyes, and normally when people are like that they do turn out to be dreadful lol
I worked a few days on this show last year and have to say how surprised i was at the amount of editing there is.
Most of the audience reactions are taken from different points of the day, most applause/boos/ovations are recorded when nothing is going on except a warm up man shouting "cheer for 10 seconds" and a lot of the close ups of the judges are also recorded whilst nothing is going on on stage.
Namo i love u but we get it already....you don't like Madonna