This is from another "anonymous" Xbox One dev.....He/she says family sharing was actually basically a time trial.

First is family sharing, this feature is near and dear to me and I truly felt it would have helped the industry grow and make both gamers and developers happy. The premise is simple and elegant, when you buy your games for Xbox One, you can set any of them to be part of your shared library. Anyone who you deem to be family had access to these games regardless of where they are in the world. There was never any catch to that, they didn’t have to share the same billing address or physical address it could be anyone. When your family member accesses any of your games, they’re placed into a special demo mode. This demo mode in most cases would be the full game with a 15-45 minute timer and in some cases an hour. This allowed the person to play the game, get familiar with it then make a purchase if they wanted to. When the time limit was up they would automatically be prompted to the Marketplace so that they may order it if liked the game. We were toying around with a limit on the number of times members could access the shared game (as to discourage gamers from simply beating the game by doing multiple playthroughs). but we had not settled on an appropriate way of handling it.