Not to Overlook: Water!!!

Not too long ago I bartended at a hopping Bar Mitzvah. Call brand liquors: Bombay Sapphire gin, Ketel One vodka, Crown Royal ...

But towards the end of the night, after all the dancing, the partying, there was only one thing they asked for: WATER.

And no, there was no water at the bar. Or anywhere else (we couldn't find a fountain either). Oh we had 2 dozen bottles of Perrier, which was running low at the end.

Is this something the bartender needs to remind the host to get? I know you'll be getting your vodka, your gin, your rum. Please, please, please get some drinking water too.