And a bit more perspective, I've got many hours of sitting around effectively AFK in various cities waiting for groups to start up while doing something else.
Back in the good ol' days, I'd have WoW open in a background window at work for random farming. My warrior has 62 days and I can assure you that they're not really my most heavily "played" alt (meaning, I'm actually doing something on them).
I think I have a screenshot floating around somewhere of one of my hunters with a session time of 14 hours. I can can tell you right now that I lack the ability to sit in one spot for that long for any reason (fun note: if I have a meeting I have to bring a "toy" along to fiddle with otherwise I can't pay any attention to the meeting), however I do live convenient to many places and the logout timer is quite liberal.
I think one recent Naxx raid at about 8:45 I said "afk, drink" and actually drove to 7-11, got a slurpee and returned and was still logged in and still prior to the raid starting.
I've also been known to paint Warhammer models while logged in before and just have the mouse/keyboard behind me and randomly hit spacebar.
Or the BC heroic that I healed on Tylista while running a 3 account mining op in Eve and Dane noticed no fall-off...
It's all about multi-tasking.