This belief gets very interesting with company phones, where 1 person pays several hundreds/thousand phones. Oh wait, that's not a person but a legal entity?
I don’t bother to update the names on their lines, so they all probably link back to me.
Family plans are pretty common here, so I wouldn’t expect too much friction.
I would absolutely cooperate (obviously through a lawyer) with records if someone else on my family plan did something illegal.
I also have records showing that they pay me for the line.
Also yes, it would be a huge hassle. The probability of that happening is small, and I’m willing to risk it like many other things in life. I only do this for very trusted people.