It's an accidental success and the game took 3 years to make. Unless they can turn around viral marketing campaigns in significantly less time, with a clear strategy for success then it's unlikely that they'll be able (or even want) to switch markets from game design to marketing consultancy.

Additionally the whole meme is pretty far from commercialisable. It's the simplicity and wholesomeness of the goose that gives it strength. It would be difficult to attach the image to a brand without killing the feel.