I just downloaded three new games to my iPhone today. My favorite game LOTRO released a massive update and I anticipate an intensive two weeks of life in the Middle earth.
Oh your son (and husband?) is also a "game addict"? That makes two of us. Actually you see, your son and I are rather normal people: 58% of Americans play video games, 62% of all gamers are adults, with average of 2 gamers per household, and 44% gamers are over 35 years old. 
Let's agree that in a game you solve unnecessary problems voluntarily.
What are we (game addicts) guilty of? We are normal human beings, hardworking learners. Let me tell you why.
First, what is a game? Let's agree that in a game you solve unnecessary problems voluntarily: Fight your way through an array of more and more powerful monsters to save the princess. Race against time to solve more and more difficult puzzles to save the world. Or complete challenges of all difficulties and defeat different kinds of players, to develop your character and gear to be the best in the community.
Lots of gamers spend lots of time and money to solve these problems, voluntarily. In the U.S. gamers spent in 2014 an average of 22 hours a week playing. 
Gamification has been here for years
Take into account an average 40-hour working week (and you get paid to do the job), wouldn't you call gamers hardworking? These "works" are addictive because the game mechanics in them have been well designed particularly to drive up motivation and engagement, to solve problems and to learn to solve problems.
The same game mechanics have long spilled over into non-gaming environments. That is what the recent buzzword "gamification" is all about. Think airline mileage membership, grocery store loyal customer membership, scout badges, Nike Fuel band, Kickstarter…
The game mechanics in them have been well designed particularly to drive up motivation and engagement, to solve problems and to learn to solve problems.
Gamification is a design practice that utilizes game mechanics in non-gaming environments, emphasizing on human motivation. As the gamification guru Yu–Kai Chou put it, "since games have spent decades (or even centuries depending on how you qualify a game) learning how to master motivation and engagement, we are now learning from games, and that is why we call it Gamification."
Gamification drives learning engagement
In recent mobile app development, gamification has been widely employed in learning apps. Using game mechanics, these apps transform a laborious and boring task (i.e.learning) into something fun and addictive. It can be learning a language, guitar playing or maths. Some weeks ago I attended a TEDx event, there were talks particularly about fun, games and learning.
From one talk I learnt about this app called DragonBox, which gamifies learning of algebra. It utilizes basic game mechanics: stars, levels, progress, milestone, collection and a simple story.
When I got home I decided to test the game on my 4 year-old son. The result was an instant gratification. He learnt to solve an equation like this within 1.5 hours. Not only it was not boring, it was voluntary, and he is only four!
"We win when learning and fun is indistinguishable." - Richard Culatta -
Richard Culatta, a White House director of Office of Education and Technology, once said "we win when learning and fun is indistinguishable." So, if you son is a "game addict", maybe he is only guilty of being a hardworking learner, only that he is not motivated well in the "real world".
Do you blame a child for getting bored in a systematically unmotivating learning environment? Or for that matter, what about an employee getting bored in a working environment? Or customers not engaged with your service?
Maybe there is nothing much to worry about. Instead, embrace the games and take advantage of them.