I can't imagine big publishers releasing AAA games DRM-free anywhere, since that would make pirating them so easy.
But then again, even with DRM it seems that games are still easy to pirate; so maybe it would make sense for them to give DRM-free a try and hope that people buy the games out of appreciation.
And they would earn much more... people who pirated before will still pirate, and people who bought the games before, will buy them anyway. Only difference, the company does not need to invest in DRM Research and Tools. Makes it cheaper for them to produce :)