I'm just refuting most of the comments as they come out.
Going off-line is easy. Turning off updates is easy. Turning off the account protection (e-mail verification) is also easy. Many other things are easy. People just need to right-click. It's all there. They have help and forums too.
Some people in many threads have said requiring Steam only encourages piracy, as people feel "forced" to use the hacked/cracked version. That's not true. Don't confuse "fair use" with "piracy." I.e., if people really only want to use the hacked/cracked version so they don't have to deal with Steam, then would pay for it at Steam, Gamers Gate, Impulse, etc..., get their legal CD key, and then use the hacked/cracked version without Steam. But since the great majority of people don't do that, it's not even remotely "fair use," but actual, real, direct "piracy." The same can be said about movies, music, etc... Pay for it, even if you somehow get a DRM-free version and claim "fair use" for doing so. If you don't pay for it, you have no "fair use" argument whatsoever.
I actually think this thread should be closed, because the overwhelming majority of justifications are inaccurate excuses. If you don't want a Steam version, fine, sign the thread. But don't make up excuses that aren't true.