I would imagine the quote "the devil you know is better than the devil you don't" rings true for a lot of people subconsciously though... People know Windows, they're guaranteed to know someone who they turn for help, and they don't feel like relearning a brand new OS so their choice is essentially made up for them whether they know it or not. And Windows fanboys call Apple fanboys "sheep"...
So you imagine the people who prefer Windows, that none of them actually have Macs or have used them? I'm sure that's true for some, maybe many, but certainly not all.