I would just borrow some other people's reasoning,
3rd party hardwares does not support OSX is because their developers are lazy and didn't write drivers
iTunes doesn't support Linux, is because apple is lazy and didn't write it for linux.
wine can only run pretty old version of iTunes, so its not useful for iPod Touch who need latest version.
Indeed, Linux is probably too "FREE" for apple since it will be difficult to close things up on that platform