I think you're overreaching in regard to graphics only attracting casual gamers. I'd argue it scares them away, mostly because casual gamers don't have $500 video cards. If anything, casual gamers rely more on gameplay than they do eye candy. I won't say graphics don't help sell a title; they do, but more people skewed toward hard core seem to worry about how pretty something is, at least beyond a basic threshold. Just because you don't care about graphics, it doesn't mean your peers don't.
The one thing I've noticed most in an office filled with gamers ranging from "hey, games are cool" to "holy God you mean you read books that aren't sci-fi or fantasy?" is the more immersed in the culture you are, the more apt you are to care about graphics. It just takes more to wow you after a while, and bragging about your FPS in Half-Life 2 is something that's decidedly computer jock.
While I still maintain we'll draw in more hard core gamers, too, I think casual gamers follow games with interesting gameplay or social aspects more closely than they do graphics. Take the Sims, for example. Or games like Tetris, or anything on Pogo. They all have low barriers of entry, yet human skill and strategy opens the door to a deeper experience.
But let's say you're right, and EA does nothing but crap out WWII shooters and Madden sequels into perpetuity. I'd wager each game is going to cost $50, and development teams will see very little of that. Why? Because EA, in order to reach casual gamers without broadband, has to buy real estate in stores like Best Buy, which drives up the price of production.
However, hope isn't lost. While EA builds EA Cambodia in order to churn out more sequels, independent developers and forward-thinking publishers will start abandoning the retail model in order to cater to the hard core, broadband-using player base, who are more than happy to pay $20 to download a cool game at 500 kb per second. Take a look at Uplink (http://uplink.co.uk/). Introversion has played the publisher game a few times, but they're left hocking their wares online. Steam is a giant leap forward in this regard, as well. The big guys will get on board with this, but it's a trail the little guys (both catering to the casual and the hard core) are going to blaze.