Not all games sold on Steam use DRM.

See: http://www.gog.com/forum/general/list_of_drmfree_games_on_st...

Has Steam ever claimed that their DRM (where it's used) is either for (A) Offline compute, or (B) MMO use?

Personally, it's not so much the DRM that EA has infected their latest games with, or not even so much that it requires a constant internet connection (though, Sim City was one of the great play-alone games left) - but that they've been too cowardly too just come out and say, "Yes, we require you to be connected to the internet to play this game so that we can reduce piracy."

Lying (or not telling the truth) about this obvious situation only makes them look bad.

Many games on Steam can be played in offline modes. Maxis claimed there was extensive server-side processing that required SimCity's online connectivity, but this was proven to be an exaggeration. In addition to a lack of local saving/loading, players have been losing their cities due to processing errors.

Steam's DRM is very unobtrusive, at least in all the games I've played. I can disconnect from the internet and continue playing a launched game, or even quit and launch a new one, without it affecting the gameplay (or ability to save). So no, Steam isn't Always On DRM, at least not how I understand the term.