I assume they only ever watched the awful 2001 version, which has a more faithful ending to the original Planet of the Apes book than the 1968 film. In the book it's also an alien planet, rather than Earth.
They probably never bothered to watch the 60s film and just assumed that they knew what was happening because the ending is so iconic and has been widely parodied for 50+ years.
Please distribute this to everyone you know on earth.
When John Glenn returns from space, everybody needs to dress in ape suits.
We have just 4 days in which to bury the Statue of Liberty up to her head.
EVERYBODY HURRY!
If that's true how did Ellis Island end up the coast with rocky cliffs and that statue is iron and copper I we meant to believe it lasted long enough for the marsh land of New York to turn into rocky cliffs and white sand... Pathetic monki