Reference designs and firmware sell silicon, but no one wants to pay for it (this applies to both end users and for the chip companies). The reasoning I've heard from the "business-types" in a chip company was their belief that Maker exposure would lead to reference firmware, drivers, etc. being written for free by users on the Internet rather than hiring and paying for developers internally.
It's a "spray and pray" strategy, not unlike the turn the VC industry has taken by investing in 400 (or more) startups. It's hard to see where the next consumer-facing hit is going to come from, whether it is in social media or a cool gadget, so it makes sense to spread a wide net, if you can do it cost effectively.
I kinda feel that I am on the wrong side when I am being skeptical about the newborn love between chip guys and makers. I see this being a new trend. And possibly a big one. And yet, for chip vendors to really leverage the power of 'makers' and 'open source' communites, there seems to be still a long way to go.