I might be twisting the statistics but people remember 7% of what they hear (or is it that 7% of what they remember is what they heard?).
Anyway - point being, if you are a conference organiser, you want everyone to leave with a great impression of what a terrific conference it was and what a great time they had there - and if five or six people start clapping but the other 126 don't then there's a 'cringe factor' that kills the feel-good factor stone dead.
Sorry. I think I've taken this thread about as off-piste as you can go - so: Now back to your regularly scheduled programme.....