Once upon a time there wasn't much to wargaming besides miniatures, and those were considered a really fringe hobby despite the interest of famous authors H.G. Wells (Little Wars) and Fletcher Pratt, who for a few brief years had all kinds of folks crawling around on ballroom floors with rulers and little metal ship models. Yeah, professional military types fiddled with Kriegspiel and other simulations, but for us civilians, it was miniatures or nothing until Charles Roberts came along in the early 1960s with what would become the first Avalon Hill games. They sold okay, other folks got interested in making games, and by the 1970s, military boardgaming was a pretty big deal.
Along about that time, Gygax and Dave Arneson came up with the brilliant idea of combining some extemporized rules for magic use with medieval miniatures rules. They put together a company, wrote up their campaign rules in three little booklets, packaged those books in a white box, and the rest, as they say, is history. Next thing you know, thousands and thousands of folks who had grown up reading Tolkien, deCamp, Leiber and Vance were rolling dice, scribbling on reams of paper, and using up small forests worth of quadrille-ruled quarter-inch graph paper. Some of them even bought miniatures and painted them. ;)
More to the point, most game players did their best to act like their characters. They played the roles determined by their characters, even if said characters were nothing like the people playing them. That was half the fun, wasn't it?
D&D got the ball rolling. After it came Traveller, RuneQuest, Warhammer, GURPS, and scores of lesser-known games focusing on specific literary worlds (Call of Cthulhu, frex) or offering a more realistic simulation of the Middle Ages than the idealized medievalism of D&D.
Still later, of course, come the CCGs like Magic, LARPs, computer-based RPGs, MUDs and MMORPGs. All this from three little books, a handful of dice, some pencils and paper, and a bright idea shared by a couple of guys from the upper Midwest. It's pretty amazing, really, and you have to wonder how many peoples' lives were changed by the hobby Gygax and Arneson got going. I know that I personally spent something like five whole years of my life on RPGs, when you add up all the campaigns I've run as a GM, campaigns I've played in, campaigns I drew up and never ran, and time spent telling (or listening to) war stories about other peoples' campaigns. On top of that, I probably spent a kilobuck or ten on rules books over the past thirty years, some of which are probably never going to be used. Not that I didn't get my money's worth out of them anyway, mind you.
Whatever criticism one might have for the late E. Gary Gygax, (and I gather a lot of gamers have plenty), deathquaker is absolutely right. Respect the man for the good he did, and quit whining already.