That's what I don't get. You say it's useful. That implies you're doing something you weren't able to before, or getting some extra utility out of it, yet, from my understanding, you legally speaking should be no less attentive in the operation of this vehicle than any other.

In fact, you let your family operate it in FSD? Are you really doing them any favors? Driving is hard enough without having to consciously override an additional source of errors. You may be unintentionally training them to operate Autopilot/FSD instead of driving safely in general.