Another observation, made in Texas the week I was there, was "On which side should the man stand while walking down a sidewalk with his companion"?
In days of old, before the advent of modern plumbing, folks used chamber pots. These were, literally, pots, often made from ceramic, wood, or stone, were used as an indoor urinal during the night. When it was too dark or cold to go outside to the privy, one simply urinated into their chamber pot. In the morning, these pots were set outside on the sidewalk to be emptied.
In those days, the man walked on the inside of the sidewalk, closest to the building, so as to avoid the lady coming into close proximity to the offensive material.
Later, as horses as a means of transport became less prevalent and the automobile took over, we also saw the decline of external plumbing and the rise of the water closet. Chamber pots went the way of the DoDo bird, and a new paradigm took hold: That of the man walking closest to the road, in the event that a wayward driver came too near the pedestrians, and the lady needed be shielded from harm.
So, fellas, let us mind our manners: When walking with your woman, you, Kind Sir, should always be closest to the road.*
(* The exception, I've been told, is if walking on the road side involves holding the lady's dominant shooting hand. My friend, C, a Peace Officer in Texas, would never walk with me in a manner that occupies her right hand... it's her strong hand, and the side on which she carries her sidearm.)