I don't see how it could have been a con, as there were thousands of people involved - from several sets of astronauts through the instructors in the training courses through the designers and producers of the physical equipment involved and the electrics and electronics needed, the communications systems, the computer programmers, the interpreters of the data being sent back during the voyages and the corrections to the programming need for minor deviations, the photographers, the radio hams listening to every word exchanged, the families of the astronauts.
Then there are the observations, reports and photographs which have been confirmed by further observations and calculations by scientists, astrophysicists and learned academics of many nations, the moon rocks brought back and studied in detail by geologists from many unrelated laboratories and found to contain elements and combinations of materials which are extremely rare on earth.
How could all those diverse people have been in a conspiracy of silence? If it have been faked, surely some of these experts and people with close, intimate contact with the project would have detected an anomaly and been very vocal about how they had been cheated? Or how could some whistle-blower have resisted publishing his inside story and getting his moment of fame?
