Saying - 'Don't worry, we've all been there' -
To a friend as their eyes swiftly expand the moment they for the first time have their minds blown into a stratospheric level of perfectly reasonable, shocked, compilation as they gaze upon a mustache as it eats the hair piece off a bald man, at festival of new vacuum technology demonstration, where one of the new technologies was hair vacuuming advancements, yet NONE of the new technologies have even mentioned, let-alone included, mustaches that can eat, or move, or that are alive - is an unhelpful, terrible and deeply cruel thing to say. Trust me, I've been there.
And yet saying 'buck up' is perfectly fine!
Sayings sure are weird.