Oh come on. The reality is that most people who get freak success are very often one-trick ponies. They don't often have a second chapter and some/most of the ones that do, do so only because they are highly driven type-A personalities who thrive on competition, which is the opposite of who Notch is, from what I can tell. Notch probably understands this and pardon me if I don't accept your morality argument over whats essentially a mild distraction (a video game).

With Notch's new found wealth, he could, say, start a charitable foundation or whatever he wants which could impact people a whole hell of a lot more people and in arguably better ways than Minecraft 2: Electric Bugaloo.