You can see this guy in an early story trailer, however he is not in the final game. He was suppose to broadcast Sigmund's voice in the Great clock as you roamed around. This concept may also be in the Insomniac Museum that you unlock if you get all 40 Zoni in the game.
(I decided to upload work from my first project at Insomniac. These are from early to mid 2009. )
The answer is actually it doesn't matter the 'tool' or the 'medium' but rather that you can draw and design. Though most of my drawings are done in Photoshop now, it is much faster then drawing an scanning something in.