I have to admit I'm a bit more cynical. Sure somethings are just private/charged for etc and access tokens are just part of a paywall. That is fair enough. I think in a lot of cases it's really about control though. Information that isn't behind a paywall, but that requires a token to access through the API. The classic example would be Twitter, when they shut down most of the third party clients.

There is of course a decent argument that it's their service and they can put whatever T&C on it that they like. However YC didn't seem to care about T&C when they funded AirBNB and defended their (ab)use of Craigslist.