I dunno, I think the pirates that buy REEL GUD GAMES out of some moral obligation are definitely a minority. Your average schmuck doesn't have such a nuanced code of ethics, they just think FREE STUFF HOLY SHIT AWESOME DOWNLOAD DOWNLOAD DOWNLOAD. Otherwise MW2 wouldn't have been pirated so many times
Any normal human being who can get something for free instead of paying for it takes the free route.
The exceptions are.
A.) People who live by some strict moral code on the issue. (not many)
B.) If there is some hint of illegality that has a real chance of biting the person in the ass. (a larger number probably)
C.) It's complex or the person just doesn't have the knowledge to do it. (an even larger number probably)
There is also always the double-stand that pirating music is okay but pirating videogames is verboten.
Obviously the reality is that a large group of people need to buy things or people will stop making them. But regular people don't live their lives based on what works for capitalistic theory.
Your best bet for reducing game piracy is to include multiplayer or community support where by the consumer feels like he is missing out on something if he doesn't do a lot of work to get that extra content.