The idea of a conspiracy centered around 50% the populace, whom are largely controlled by their reptilian ancestry, is pure ridiculousness. They would all have to have a common motive, a complete set of "in languages", jargo, and jokes. Likely they would be made even in public, sometimes by those the joke is about. It would almost be as if 50% of the people in the world were by nature emotionless and the other half not. A ruling class at all levels, and a secret slave class too duped to realize they are slaves.
Thats just pure crazy. It would be like if we put half of society down and made them perform mundane tasks for food, board, and occasional festivities to make sure they don't rise up. Given the overwhelming response we've seen to our boards, such a thing is beyond imagination. Again and again we are confronted by round earther after round earther content to "know" what we believe before we tell them, and again and again, they are always correct in their initial judgement! So much so that oft they must hurry to the nearest exit, lest they embarrass us for our lack of civility in their sight and rightly so. To work with such as us must strain the higher mind due to our sharp language, wild mythologies, and shrill tones and they have indeed given us grace by their presence.
As such, I hereby show that not only is a conspiracy beyond belief, even at a minute level just to fake a few things, but that these crazy "Lizard folk" conspiracies are just right out. Hopefully this will stop all those lizard threads we've gotten over the years.
EDIT: Since some are thick in various aspects, it is to be directly stated the lizard conspiracy is to keep the earths shape secret.