I think I might jump in on this thread.
Some people that play this game are retired, disabled, and various other sorts of things. Me for one, I had a life threatening sickness last year that left me so week that all I could do was basically sit. This game was a life saver for me since I don't watch TV.
I like many others have grown kids that do not need my regular attention, and my wife for one, is just happy for me to be alive, so seeing me sit and do anything makes her happy. This is one reason why I log so many hours.
I know this thread was not about me, but when looking at the hours some people play, it may not be just an addiction, there may be many other factors as to why they spend so much time on-line.
Just putting out some thoughts.
BMWgs