It's also something that has to do with self-control.
Just like eating.
Gaming, to my understanding, has become a retreat for me over the school years. When I become depressed, I'd run off and play video games after school. I rarely do regularly, and I wish I could just admit that I have time to do something meaningful with that "I don't care about life" time.
Video games and drugs get you away from reality for awhile, so you can just go away. It's an adolescent's anti-drug.