Like so many conspiracies, people who are prone to believing in them take a simple fact out of context and then add their own plausible, yet believable, ideas.
Much like the alien spacecraft seen over Area 51 20 years ago. Amazingly drawings and pictures of what people saw look amazingly similar to the Stealth fighter and bombers of today.
Do conspiracies exits? Absolutely! Are there aliens? Most likely. As a race we would be pompous and self-centered to believe that in all the universe we are the only intelligent race. Did we land on the moon? Yes! And for the love of God please let that one rest, because the conspiracy makes no sense. Was Marilyn Monroe murdered by the mafia? Possibly, who cares! Was JFK shot by more than one person? Very likely, and it may have very well been a planned hit.
Conspiracies exist, and many of them for a reason. Think about the fallout if full disclosure were the norm for governments around the world. Do you really want to know if our planet is at risk of alien invasion? How safe would you feel if the public knew how the mafia could reach out and kill someone as high-up as the President?
Some truths are hidden in order to keep the piece. While in the military I was privy to many bits of information that before had been unknown to me; information that the general population of the world does not know. I can honestly say that for years I had trouble sleeping as a result of knowing "what is really going on". Today I live blissfully happy in a self-indulged world of information isolation. What I don't know, what I have no business needing to know, has no affect on my family or me.