It's weird to consider how tied-down network TV was back in the day.
I remember that the simple sound of a toilet flush was a wildly hilarious gag on "All In the Family", partly because it was so unexpected. I remember that most people think "Brady Bunch" was the first time a married couple was shown in the same bed (
google research shows it wasn't the first, but that people thought that, just goes to show how rare it was).