Sure, maybe your NoSQL solution is open source and freely licensed, but if the implementation is so incredibly specific, and you can't easily port your application to another provider, what does it matter? You can't port, you can't switch vendors, and you're locked in. NoSQL is a mess, and the only way to clean it up is to get some standards in place. Sadly, venture capitalists don't like standards, because, well, it stops you from being locked in.