Precisely what that addiction is to is perhaps what's hardest to answer. Is it attention? Validation? Some more abstract notion of amassment and score? I've noticed myself looking up into the corner upon return to the site, and have even consciously avoided that gaze pattern at times.
It may even come down to such fundamental questions as the existence of altruism. Just as one can ask "are you doing this for someone else, or just because doing things for others makes you feel good?" one can ask at "are you contributing thoughtfully because you want to participate in the community, or because you want to see your karma go up?" If you want to see your karma increase, is it because you want to participate, or the converse? Can the two be functionally separated?