Can we seriously stop with the "developers get no money from used games" nonsense. It's one of those things that is technically true but totally missing the point. Although developers do not gain from the actual transfer of ownership from one party to another, "resale value" is a fundamental property of nearly all physical property that is sold.
As such, it is something that consumers consider when making a purchase, and as such, it is something that the developers DO in fact benefit from. The mere existence of such a large market for used games proves that many purchasers of games do so fully intending to resell at a later date. Therefore, if resale were not an option, game sales might potentially decline, or prices would have to be adjusted.
For example: If someone buys a $60 game with the intention of selling it for $20 a couple months later, that person is really only spending $40 worth of funds (ignoring the time value of money for such a small period and given the average gamer doesn't necessarily have a well constructed stock portfolio). Theoretically, if that developer were to offer the same game, only WITHOUT the ability to transfer ownership, that customer would only be willing to pay $40 for the game.
Wow, it's rare that there's a Muffin post that I 100% agree with, but these things happen.
I hate the argument that used games are "worse" than piracy. Resale value is totally a component of the value of anything you buy and games are included. The sales of used games don't give developers money, but the existence of such a market does benefit them, even if they are way too short-sighted to realize it.
I would say the same thing is often true about piracy as well, although pirating brand new games instead of buying them is overall a harmful practice. However, so is draconian DRM measures to counteract it.