Why is it weird to say? The astronauts were people with a sense of humour. Young and Duke particularly were noted for their continued amusing commentary while on the Moon. It's a joke along the lines of 'maybe it was Santa Claus'.

__________________
"The very powerful and the very stupid have one thing in common: They don't alter their views to fit the facts, they alter the facts to fit their views." The Doctor, Doctor Who: The Face of Evil.