Concept art by http://www.johanvinet.com/

You would think that the idea had come up before. Maybe no one wanted to execute it?

It's because of the creator of Calvin and Hobbes, Bill Watterson.

He refuses:

Bill Waterson is sort of famous for being a bit of a hermit. He rarely, if ever, grants interviews, has never licensed out his work, and lives in New Mexico. By all accounts, it's safe to assume he wants to be left alone.

But, that's the beauty of a democratized Internet. Fans can pay tribute to a creator's work while still respecting the creator's wishes. It's not like these guys are profiting off of this, they just wanted to pay homage.

This 8-bit, 'what-if' start screen is a perfect example of a fan-made tribute by Johan VINET:

Found it on his Tumblr: 

http://johanvinet.tumblr.com/post/23535804010/calvin-and-hobbes-what-the-16-bit-video-game

A few more: