After the MacBook came out, but before the new Chromebook Pixel, I was telling people that Apple only put a single type-C port on their MacBook for this reason. I said "When PC's come out with type-C, they'll have multiple ports, but you'll only be able to use one of them as the power port. Apple would rather have a single port than have such a confusing setup."

Of course, then the Chromebook Pixel came out and proved me wrong. I still expect some PC makers to try and shave costs by only supporting power input on one of the type-C connectors, but the Chromebook Pixel example will ensure that such an arrangement will get slammed by reviewers.