lol yeah I was addicted to mmo gaming in high school, had carpel tunnel so bad I couldn't sleep. You actually get such an adrenaline rush and don't feel like eating/drinking.
In some ways it was better than getting in trouble, and there would be 30+ teammates in your vent/skype channel any time of day from dozens of countries. You get to know each other and there's some community.
It's bad, but so is being beat down and bullied by real people coming at you on a personal level. I think that's worse, if school shooters were addicted to games they'd be too busy to fester that level of hate.
Gaming is what got me into programming, specifically. Which has been the most rewarding aspect of my life. Actually, most game developers start as gamers.