The argument from 'people are inherently good, and once they've realised they like it will buy the product' is fine until it runs up against one crucial barrier.
People are not good, and the vast majority who get something for free will have two things happen to them.
1. They will not then spend money on something they already own, illegally or not, for free.
2. They will develop the entitlement complex so noticeable, especially amongst gamers, that they somehow have a right to the luxury items. Since they own a 360, but don't now have the money to buy more games for it, of course they should pirate those games! Otherwise what would they use the 360 for?
Pretty much anything besides food and shelter is a luxury. If you are a good person fine, bully for you, I hope you have much fun with people who honestly believe that people won't take something for nothing.
Humans are selfish, greedy, entitled bastards in every way though, and the occasional nice guy doesn't balance them out.
Remember that Indie bundle that sold for any price, as long as it was some money? Yeah, also remember when a rather large number of people still pirated it? There shouldn't even be a fucking argument here.