Oh my grandfather had several (ok, really 4 jokes) that he told over and over.
One was that someone (forgot who) said sneeringly that Scots ate oats while the English fed oats to their horses, and the Scot replied that was why the English had such fine horses and the Scots had such fine men.
The only reason that is funny is that I can see in my mind my grandfather being so happy and pleased when he was telling it. It amused him always. At the time — which was when he was eating oatmeal, I’m sure I rolled my eyes.