To some degree though there is education, early FPS games and even games today, hell look at Minecraft and Garys Mod, both inspired from modding games they grew up playing. Todays modders are learning useful skills, photoshop, programming, design. Just to name a few. So while a majority may end up getting dumb entertainment out of it there are those that it will spark interest in.
I wouldn't be interested in computers today if it weren't for Doom and Quake and my using crap programs written for those games and thinking I could write something better. Or my simply playing them at a time when you actually had to set IRQ's manually.