Another reason having to do with economics is that an educational arcade game would often lack the dynamics or flash needed to sell a good deal of copies. Yes, you could program a game based on The Grapes of Wrath, but the newest movie by Jean-Claude Van Damme might interest the demographics of the video game market a bit more. The biggest reason that I think video games should stay violent is that they let you do something that you can't do in real life, which is the whole idea of virtual reality and simulation anyway. If you want to unwind after a tough day at work, you wouldn't want to go out with an AK-47 and destroy a McDonald's. However, you might want to go to an arcade with a couple of dollars and sit down at an X-Men console and fight a few hundred bad guys, then leave thinking about your game and not your worries.
Games are just that, games.
They are diversions to let your mind relax or expand, something that many people who are too technophobic to appreciate the computer and its recreational uses simply don't understand. Once again, a group of people can't understand what their children can purchase, so they are stopping it. The people who are afraid of the counter-culture and don't understand the advancement in technology want to limit life to their own experience. Unfortunately, video game manufacturers chose to comply quickly, making this a battle lost for those supporting the future of the video game industry. Hopefully the current generation can realize the limitations being imposed on the technology of the future before they get even more outrageous and limit some of the opportunities the world of tomorrow can bring us.