LeeS:
I cannot speak for what "REAL MEN" shot where you grew up and cannot speak for what you saw as a child.
I can speak from what I lived and saw.
I grew up in the real South. Georgia to be exact and near the South Carolina line.
I don't think that any man, then living, would consider either of my grand fathers to be other than real men.
They had more than one gun and used them as they were intended.
For bird, both used 16 gauge guns and would say that a gentleman would not go afield with a larger gauge gun for bird. Bird was meant to be Bob White Quail.
The larger gauges were for ducks.
I do not remember many 20 gauge guns, but do remember 410s that were used for rabbits and squirrel.
These men were born in the 1870s, so much of their thinking carried over from the times that the 10 gauge was the heavy gun and the 12 gauge was the light one. The very light 16 gauge was a bow to modernity.
I do think that there was a different thinking in the North at that time.I am speaking of the 1940s when I grew up and became conscious of shooting and hunting.
Best,
John