This evening I have been reminded that my parents and theirs had a weird rule that children were not allowed to sit on the sofa. We had to sit on the floor unless we were invited to sit up on the furniture.
I also remember if we had family over for dinner, children had to sit at a different table, and if there was ever a buffet, children were last to eat.
I have never enforced any of this with my children.
What stupid rules were there when you were a kid?