well, telling someone off really doesn't accomplish anything. it mike make you feel better if you allowed yourself to lose your cool in the first place. the whole thing just derives from the naivete of folks who don't realize they are at the mercy of the airline for everything, and to whom lying comes as a surpise. I've never bothered to tell these jokers off even when I knew their statement to be false because its as likely that someone lied to them and they are just repeating the best information available to them.

There was a very interesting thread on FT about why airlines deliberately lie to pax. It turned into a raging debate about whether such lying occurs, with those with status defeding the airlines and other pax claiming bloody murder. So the debate was not resolved but many interesting anecdotes retold along the way.