1) There are some fast wides that have f stops like f/1.4, f/1.8, f/1.9, and f/2.0.
2) F/1 wides would not have much of a market, and they would be entirely unaffordable for most people.
3) Wide lenses do not need to be as fast as normal or long lenses, because you can get away with slower shutter speeds without capturing a lot of camera shake. For example, my 28mm f/2.0 lens can gather just as much light hand held as my 50mm f/1.4, because I can reliably shoot with it hand held at '30.
4) Perhaps super fast wides are extremely difficult to design in a way that provides good-enough optical quality. It was hard enough even with Canon's EF 50mm f/1.0, a normal lens, which is relatively simple to design.
5) Looking to the future, the need for new fast lenses decreases every time a new generation of digital cameras with higher and/or cleaner ISOs comes out. With what I tend to shoot, I need my 1.2 lens for film, or for my 8-year-old 6 Mpix ISO 1600 maximum (and a dirty 1600 at that) 10D; the f/1.0 would be ideal, but I cannot afford it. But I will be able to get by just fine with a 1.4 lens when I get my next digital camera, a D700.