Why did Johnny Depp team up with HarperCollins to launch a book imprint named Infinitum Nihil?

So you’re Johnny Depp, and you’ve decided you want to get into the publishing business. Do you (a) leverage your fame and contacts, invest, and set up a lean, indie publishing company that takes advantage of the latest technology? Or do you (b) team up with HarperCollins to launch an imprint named Infiniti Nihil? Apparently you choose option (b), but why?

The two titles announced for Infiniti Nihil so far are a book about Bob Dylan, and Woody Guthrie’s recently rediscovered House of Earth. It’ll be interesting to see how involved Depp is in the publishing process. Is this just a branding exercise, or is Depp more deeply involved?

I guess going with HarperCollins is the safe option. But wouldn’t it be cool if someone like Johnny Depp decided to launch a venture like this and struck out on his own, without the backing of a traditional publisher? It’s bound to happen, isn’t it? At some point, a superstar name (more like an established author) is going to say “Fuck it” and take his or her books off to KDP Select and Smashwords. It makes sense. So why hasn’t it happened yet?