What's wrong with proprietary software? Also, I'm not fond of his philosophy when it comes to programming. Not minimalist enough. Everything is bloated.
Paying money for a computer with software is legitimate when the software respects the user's freedom. A modern example of this would be the Linksys WRT54G, Linux is installed and the development costs of changing modifying Linux would be included in the cost of purchasing this machine.
It's a bit silly when most people are just going to install DD-WRT or OpenWrt instead of using the distribution that comes with the router, though.