How would a family stop duelling devices? If any Chromecast enabled application can work, and you have four family members each with a device, ... anyone with an IQ over 80 can see where this is going.
With AppleTV you have one remote to rule it all. Not with this thing... anarchy in the living room.
Obviously, there has to be some form of pairing taking place, which never is as quick and smooth as people say it is. But if there isn't, Lord help the family.