Why is it logical to presume all the geeks would/should switch to OSX/Apple?

1) it doesn't fit with classic geek- you pay a lot of extra money for shiny hardware. Classically, a geek did it on the cheap and 'hacked' something together.

2) I consider myself pretty geeky, and yet I run Windows exclusively now. (and my servers run Linux, and I agree with OSX for media computing) Why is this? Well, to start all the tools I care about run on Windows. CAD programs, Matlab (USED to work on OSX. Key word USED), development tools, and to some extent games.