I think it should be classified as a disease...
Our PC ways keep our language constantly in flux.
No kid is going to have DTs (like heroine withdrawal) if they ended up on Gilligan's Island/Lord of the Flies after a three hour tour. They may act like a unrelentingly spoiled dickhead, but that's the kid and his parents doing - not video games.
...and yes I go with the Tommy LaSorda definition of alcoholism not being a disease.