Happens more often than you might think, I always appreciate the heads up, and would much rather fly without water than be delayed or cancelled, the other day I took a six am flight with no water, the fa came and said he was very sorry he was unable to serve me coffee but he had reported it and I would be getting miles which I actually did, I was amused since I didn’t ask for coffee nor do I ever drink it on a plane, oh and this isn’t an american isolated issue, I actually think the bathrooms can be used once you are in the air but there is not water for handwashing we were provided with towelettes