I've had quite a few problems with DRM over the years, to the point where in the early 2000's I would crack every DRM-laden game I installed as a matter of course.
Most memorably, I installed Microsoft Games for Windows so I could play Batman: Arkham Asylum and several of the other games already installed on my computer stopped working. So I played straight through to the finish, then immediately uninstalled the game and GfW. Somehow the other games started working again. After that, I swore off these glorified DRM-as-a-service systems (I'm looking at you, Uplay and EA Origin) especially when they require a login. It has definitely limited my gaming options, but I'm honestly not that bothered about losing out on many AAA games, but services like gog.com and humblebundle.com have a lot alternatives on offer as long as you're vigilant about checking for the DRM-free games on the latter. It turns out there is still a ton of indie stuff out there that I have really enjoyed now that I'm paying more attention to that space.
When Steam started I actually did the work of reading the EULA and privacy policy, reading up on the limitations of offline mode and on Valve's promise to make the content available after Steam one day dies, and ultimately made the decision to trust Valve's platform and DRM. The alternative at the time would have meant giving up on Counter Strike and Day of Defeat, so that influenced my decision in no small part. In the end though, I have to say that while I'm not always cool with what Valve does, I trust the other publishers with their own combination digital storefront/DRM services far less.