There was at one time a Penumbra tech demo before the game came out, which was free. With the Humble Indie Bundle you used to be able to pay as low as a penny (I think it's changed now), but that's seen as a pretty low move if you can afford to pay higher. I agree that it's pretty pointless to try and argue with those over youtube though. That part of the internet tends to have more irrational, for lack of a better term, morons than a lot of places. As Mark Twain once said:
Quote: "Do not argue with an idiot, they drag you down to their level and beat you with experience."