GoG (drm free) is the alternate store to steam (DRM) and frankly the only few stores that could even go against Steam as a option. The gog Galaxy client is optional but for the witcher card game which uses there servers, downside they in the past pushed it a little too hard. they should have realized most steam users would use it while GoG users would or wouldn't use it. and not try to push everyone to use it but they listened at lest.