I get the impression that this game was built because he wanted to build something he himself would enjoy, not something he could become rich off. Maybe there's something to that philosophy ;)
It was tongue-in-cheek.
It's genuine fun, different and has QWAN.
(This post started out about being about being willing to ignore conventions, but drifted somewhat into the nature of gameplay, sorry.)
This is the first time I've seen him referenced "in the wild"
He also is responsible for Left 4k Dead (another contest entry) if you remember that from a year or so ago.