When I saw the can design I immediately thought that it looks like the art style of "David Boring" (https://en.wikipedia.org/wiki/David_Boring), turns out it was really Daniel Clowes who designed it. "Ghost world" is one of my favorite stories & movies as well, but I didn't hear about O.K. soda before. Fascinating!
While I really like the art style and dark touch I think it was probably too niche or too off-putting for most people.