The majority of people want to go into a store, buy a computer, and have it work. They don't know or care what an Operating System is, as long as it runs the store-bought software they want to run on it. Giving people a half-dozen different combinations of hardware and software is only going to confuse them, prompt them to buy the cheaper product with DistroOfTheWeek Linux on it, and return it because it doesn't work the way they're used to. I could be mistaken, but I thought Dell tried selling systems without operating systems a few years back and gave up on it because shockingly, nobody was interested.