As Electronic Arts and THQ make the move to get a piece of the secondhand sale market with the strategic use of one-time use downloadable content codes, a Sony Computer Entertainment America exec expressed his own reservations with the used game market."I have very mixed emotions about [one-time use codes in new games]," said SCEA SVP of publisher relations Rob Dyer in a new Gamasutra feature interview . Sony has yet to use these codes -- meant to coax players into buying games new -- in its own new game packaging."I am a big believer in encouraging the gamer to have a reason to hold onto [a game] and to continue to play, and for the publisher to be able to see something if there is a second sale," Dyer said, "because right now, for years, as a publisher, we saw nothing [from used sales]. Very frustrating."Third-party publisher EA is spearheading a new trend in the game industry that has publishers including a one-time use code packaged in with new games. The original buyer of the new game submits this code to an online storefront like PlayStation Network or Xbox Live in exchange for downloadable content or features.Used game buyers (assuming the original owner already used the code) will have to pay extra to gain access to this content. In the case of EA's Online Pass, used game buyers will have to pay extra for content and online multiplayer access.THQ has adopted this method for online play with its newfighting game, and Ubisoft said it was watching EA's tactic "very carefully."It's part of publishers' efforts to grab a piece of the substantial used game market -- a market in which game publishers do not see direct revenues, only retailers like GameStop."As a first party, I understand why there's a second sale, but I'm not always excited about it. Look, this has been a tough couple of years," said Dyer. "People have not been making money, and I think the used games business has been having a huge impact in that.""I'm happy to debate merits, pros, and cons with folks at GameStop and have that discussion because again, I've sat on the other side and I've seen what can happen. People need to see a way to monetize that second sale," he said.For more from Dyer on downloadable content, PlayStation Move and third-party software, read the full Gamasutra feature , available now.