In an interview with games.on.net, GOG's head of Marketing and PR Trevor Longino explained that they have been able to succesfully leverage being DRM free as a selling point, not only to gamers, but to publishers.
Trevor actually relates their experience with EA. When GOG approaches big publishers like Ubisoft, what they usually do is show them their sales figures and explain that this is what the publishers will get for their games. By pitching to each prospect the sales data from the last big publisher, they were able to grow their service one major publisher at a time. When they shared this information to EA, EA relented, and of course ended up building their own DRM loaded digital storefront, Origin. However, EA eventually relented, and joined them around eighteen months ago.
Trevor details that EA was acting like they weren't interested in the money because they didn't want to deal with GOG, precisely because at that point they were still a small company. Of course, EA found themselves late to the party as GOG was already big business, signing up many other content holders like ,Activision, Interplay, Atari, Epic Games, Apogee, etc.
When asked about Steam, Trevor relates his personal experiences, with how easy it is to play games, but had problems buying them whenever he travels to Poland. He concurs that Steam is popular in spite of DRM because of the frequent Steam sales, but also because they provide an attractive package with the added social features. Ultimately, he reasserts that GOG is still opposed to DRM on principle, but says that they would never 100 % rule it out.
