1340
Nobody says it anymore
(startrek.website)
I've heard it explained that "hey" used to be more of an urgent way to get someone's attention, rather than a casual "hello" like it is now, so it sounded rude to some older folks.
Was there really a cause behind that? I always thought it was people just being silly.
It could also have been just that - an old joke that everyone liked responding with when they had the chance.
That is how I always perceived it. I can't even imagine someone saying that with a straight face as a correcting rebuke.