The creation of Diablo III's real money auction house for trading items was "definitely a design decision" rather than a commercial one, according to the game's lead designer Jay Wilson.
The auction house, fully integrated with the game, makes Blizzard the first mainstream gaming company to officially permit, and enable, players to sell in-game items to one another for real-world currency - a common practice currently dominated by grey-market 'gold farmers'.
Blizzard will profit from the auction house, collecting a flat-rate fee for every item listing and sale. But Wilson told Eurogamer that its creation was motivated by a desire to give players a service they wanted and improve their experience with the game.
"It was definitely a design decision," he said. "Certainly there's an economic element to the auction house for us, but it came first and foremost as: what do we want to do for the players? What service can we possibly offer that would make the game experience better?
"If we make money on it that's great, we're a business, we want to make money," he added. "But not at the expense of the customers - but because we've offered them something that was worth their money."
Wilson said that the lack of a proper trading system had been "a massive, gaping hole" in the Diablo games to date. "Trading is not very good in Diablo, and yet it's a game about trading. Trading is the way you get the best items in Diablo. And yet there was no trading mechanism to speak of... We wanted to focus on filling that hole."
He denied that the introduction of real-money trading had influenced the game design at all. "We really feel that the auction house is the best design for the existing item system we already have," he said. He was also sceptical about the idea that the ability to sell items for real money would change players' relationship with the game.
"I actually don't think it's going to change players that much, because it's already true," he argued. "In Diablo II, items have a real monetary value, it's just a little bit more difficult to do it. For the community that is hardcore enough to get those items, the value of them is very real.
"I think there's a perception issue where people might think it's going to be different, but I think in actuality it's no different than the way things are right now - other than it's more secure, it's easier, it's more fun, it's more integrated into the game."
Wilson believes that only very high-quality items from long-term players will be listed on the auction house, but he admits that no-one knows for certain what the consequences of launching the service will be.
"One of the reasons I'm really excited about this feature is, we don't know exactly what's going to happen. That, for us, is very cool. We haven't been in that position for a while where we were going to put something out there that felt very new to us, like new ground. So we're very excited to see what happens."