Sounds like Netflix needs a "Falsehoods programmers believe about families" list.
Trying to shove societal concepts into SQL tables never ends well.
a german public tv license is per household too and would not include the hospital patient either. and of course, they get plenty of complaints about edgecases as well.
if netflix wanted to sell to families, they could do that by somehow letting you specify who the familymember is, and how they relate to you and limiting it to a number of people.
These are not decisions by programers. These are business decisions.
They are trying to find a way to part as many people with as much money as possible but not more. If they err in one direction they leave money on the table, if they err in the other direction they start losing subscribers.