The Teetotaler Club Prank

Here's the idea: gather about 400 of your nearest and dearest non-drinking friends and line up first to get into a club. From there, it's a simple matter of dancing and having a good time without hitting the bar, except for water. I can imagine the club owner being suspicious of the very low takings for the night and the bartenders having no explanations at all.

Mokalus of Borg

PS - The prank payoff, unfortunately, has to be imagined.
PPS - There would be some interesting facial expressions from the bartenders on the night, though.