hucklebarry: 1. DRM.
2. SPYWARE. (I'm not going to find it for you, read the EULA).
3. auto-patching unwanted patches to games
Please, tell me people WANT DRM that use steam. Tell me that it isn't an unwanted side affect of the features they actually do want. ;) You can tell me that if you want... but you'd be very wrong.
You != most people.
Most people are fine with the DRM, because they don't give a crap about it. They don't see that as a DRM, but as a feature through which they can always chat with their friends, see their achievements and stats, compare their profiles with people from other parts of the world.
Most people are fine with the EULA, because they don't care if a message pops up once a month and asks them for a survey, which they can easily say no to.
Most people are fine with a tool scanning the currently allocated memory in order to block hacks and cracks for various VAC games.
Most people are fine with and love automatic installation of patches. Not to mention, one can always disable that for any game that he wants to.
EDIT: I really am trying hard not to laugh at the SPYWARE reference. :)