Sure, theft (downloading from torrent/ed2k) would be an easy way to get a windows version.
I want to buy the Linux version to support Linux game development, but there's only a Windows version to buy and a 20€ download of the Linux version. I feel cheated (there are places like
http://www.linuxgamepublishing.com who do sell Linux boxed linux games), but well...
Besides not wanting any binary blobs in my kernel, the opensource driver just works better for me in everyday use and involves less work.