I agree with @icehearted and @commasplice; I hate the Steam system. Sure, you can use Offline mode...if Steam feels like it. I swear, EVERY time my internet has gone down unexpectedly, Steam absolutely refused to function in offline mode.
Also, there's the fact that sometimes Steam likes to start patching the game I want to play, so I have to wait for it to finish. Or, if something happens to my connection during the patching process, then I'm shit outta luck...I can't play a partially-patched game in offline mode.
Steam is also responsible for me pirating my very first game: Half-Life 2. I bought the game while I was in the military, and I didn't have an internet connection in the barracks. So, there I was with my brand new laptop and freshly purchased copy of HL2, and I pop it in the drive to install it...and no joy. You needed an internet connection to play.
There was supposedly a phone registration option, but the half dozen times I tried it (over two days) it was either busy, or didn't ring at all. That falls into the category of "Go fuck yourself, Steam". Luckily, my roommate had had a pirated copy for TWO WEEKS. He burned me a copy so I could play the game I had already purchased.
Here's the rule of thumb for DRM: If it's easier to pirate a game than to purchase it legitimately, then people are more likely to pirate it. If purchasing a game is simply a matter of popping a DVD in the drive, installing it, and playing...then people will probably do that...especially if installing the game ONLY INSTALLS THE GAME. When I purchase a game, it's not a free license for the devs to set up shop on my computer and install whatever crazy shit they feel like.
A DRM system like the one UbiSoft was failing with isn't even the pinnacle of inconvenient...but it's getting there. I don't normally like to see companies fail, since there are undoubtedly many good people there who would lose income for a decision they had no part in. However, the only way an industry will learn a lesson is if they see one of their number fall flat on its face due to an absurdly stupid decision.
I hope UbiSoft loses enough money to become a cautionary tail for the rest of the industry...but that won't happen, so I'm going to go play some DRM-free games from GoG, because that's how I roll.