Piracy rarely affects the multiplayer usage of video games, meaning most people are pirating single player games, or at least the single player part of them. I can only believe that the people who pirate single player games only do so in order to play a single player experience. From here, we can conclude that people only pirate because they don't believe that the single player experience is worth 50-60 dollars. If Valve were to implement a rental system, either similar to gamefly or blockbuster 7$ for a week, I think a lot of piracy would be stopped. People don't ENJOY going through the hassle of pirating a game if they could buy it, but they don't want to pay 60$ for a 10 hour experience. I think that if steam could put time locks on the game (like they do there free weekends) a lot of the piracy issues would stop. Pirating a game isn't a fun thing for the consumer, but it's more fun than feeling like you wasted your money.