Because he comes out with stuff like this:
“Setting up a server is like playing an old Infocom adventure. It’s an endless series of puzzles and even when you think you’ve solved them all…you’re eventually totally screwed because three months ago, you didn’t FEED CHEESE SANDWICH TO DOG.”
…in a blog post. A blog post that NO ONE IS PAYING HIM FOR. Giving away good lines like this is a piece of largesse that other freelance writers would baulk at, trust me.