In fact I think remember hearing (in When We Left Earth) one of the Mercury astronauts say they made a military pilot's salary (which while not bad, probably wa

In fact I think remember hearing (in When We Left Earth) one of the Mercury astronauts say they made a military pilot's salary (which while not bad, probably wasn't in line with what they were doing) so they sold those space mementos to put their kids through college. They weren't trying to get rich, just trying to do what any reasonable parent would do.