The realistic goal of DRM isnt to stop piracy. Its to reduce it and delay it.
While there may be some people who still hold on to this belief, I really don't see any practical reason to espouse it. There's never really been any strong empirical evidence that DRM actually works, even to combat day-1 piracy. Really the only metrics we have go by are how well a game sells, and the verdict there is pretty conclusive: there's no correlation between strong DRM and high sales.
What DRM does is it gives copious amounts of leverage to the publisher over their customers. As a consumer, I'm not comfortable with that lopsided relationship.
Actually in the case of day-1 piracy specifically, there is. It's fairly easy to measure if there's a working zero day pirate release. That's why Ubisoft sticks to their outrageous DRM - for that goal, it works. There's releases of stuff like Assassins Creed 2 up as zero days, but they don't work properly. Of course it also costs them sales because it's so ridiculous that people (like me who STILL hasn't bought Settlers 7) refuse to buy from them, but they get what they want out of it.
But it's all besides the point. iTunes DRM is really easy to remove, and it has nothing to do with why iTunes is so successful. It's successful because it makes doing the right thing really really easy. Easier then piracy even! You get your songs on your iPhone and your computer without any particular though being required. People like that.
Similar to how Canadian ISPs reported this year that P2P traffic is down overall (and Bell is ending their wholesale traffic shaping) - that traffic is being replaced by Netflix subscriptions because again it's really really easy. No fiddling with Bittorrent, port forwards to get better downloads, or trying to figure out if the site you're using is full of malware or not. Push the button and the movie starts. That user experience is beating both pirate downloads and movie rentals because it's easier.
Steam is the same thing for games. Buying games is simple. There's no worrying about patches - Steam does it for you (some power users of long games don't like that, but you're the 1%). I don't need to find downloaded files to install it, Steam just does it (compare the GOG experience with a big game like The Witcher 2 vs Steam's install experience and it's not even close how much better Steam is). If I want to play on another computer, an ever increasing number of Steam games give me cloud saves that don't require knowing what "cloud" is in order to use them. And yes, all my games are in one spot.
That people still want Steam to have centralized control of all their games boggles the mind.
Not if you're a UI guy its not. Once you stop talking to power users and start talking to people like my mom, it becomes blindingly obvious why that's a good thing. Most people want to fuss with this stuff as little as possible and just get to the game. They don't care about the other stuff (unless it bites them, which is pretty rare), and they don't care about technical differences so long as the first solution is good enough (which Steam is). Centrally managed games means one app to learn instead of several, and that's a feature.