Using the lemming theory to say why Windows users use Windows is self-delusional. Also, I have worked supporting PCs and Macs for over 10 years and to say that Macs do not have the same types of issues that Windows based PCs do is equally self-delusional.
Windows users use Windows PCs because they are cheaper than comparable Macs and there are more applications available to them. The reasons for both of those are the business approaches that Steve Jobs and Bill Gates took selling their products. Jobs thought he could charge developers for tools and licenses to develop on "his" computers (hardware) and software (OS). Bill Gates didn't have control of the hardware and for the software Microsoft gave away tools to developers to develop applications on Windows.
Hmm, wonder why there are more apps for Windows? Hmm, wonder why there are more PCs and PC manufacturers out there and therefore prices are lower? Yep, must be all those stupid Windows users don't know a good thing when they see it.
Windows: Never bad enough to sell Macs by Default