I spoke to some classmates on our way to CeBit about DRM. All of us agreed that registering online is something all of us were perfectly fine with.
You're getting sidetracked by DRM. DRM and registering the game online isn't the issue with people against Steam in this thread. While we all would like that not to be a requirement it is for most games even those from Stardock (if you want updates/patches). I don't have a problem with having to do this.
The problem that I and most people have is this requirement to have Steam/Steamworks running all the time to play a *SINGLE PLAYER* game, even in "offline mode" it is still running.
Again, no problem with Steam needing to be running if you want to go online and get patches, play multiplayer or whatever. The problem is it running in a primarily single player game.
And then there are mods. There has been no confirmation weather mods will work outside the Steamworks system (in other words downloading them from Civ Fanatics or something). If mods have to be approved by Steam that leads to whole other issues. And what about 10 yrs from now? Will Valve still have staff to approve mods? The thing about Civ games is they are played forever. Civ 3 still has an active mod community let alone Civ 4. Heck, there are still people that play Civ 2 to this day. So will Valve still be around 10 yrs from now to not only approve mods but to keep the game alive with Steamworks so heavily embedded in it? This isn't your FPS game that gets tossed in the trash heap 6 months after it comes out. Civ is *different*.
And another thing about mods, many people have several different patch versions of Civ installed to run various different mods, some of witch may not work with later patches. No way you'll be able to run multiple versions of Civ 5 with Steam. Just not possible.
And sure you can set Civ 5 to not auto update, but my understanding (and it could be wrong) if you go online with Steam for another reason, say to play another Steam game, it will detect there is an update to Civ 5 anyway and will force you to update it before you can play again. There is back and forth on this one on other forums so maybe it's not an issue, maybe it's not.
But it's certainly possible technically which is another reason why we don't want Steam required for a *SINGLE PLAYER* game. Sure, if you want to play multiplayer it's good to have everyone on the same version. Fantastic, no problem with that. But again, for a single player game there is no need.
I could go on but why bother, those that are Steam lovers just can't see it from the other side. Steam is great for many games, especially all these shooters. But for a primarily *SINGLE PLAYER* game it's uneeded and frustrating.