Aunt Jenny's city cousin, perhaps.

"Live and learn" is an expression uttered in rue after a setback, an attempt to find a fleck of positive news in the steaming pile of failure. Well, live and learn, I'll never ride my motorcycle one-handed again. And so on. I don't know how it's intended here, except to suggest that knowledge naturally accrues as one expends one's mortal allotment. Which obviously isn't true.

Even if it was, that’s a pathetic thing to claim as new knowledge. Unless you were getting sore tendons from sawing away at the frankfurts.

Pops doesn’t want to feed them to company. He regards them as so special they’d be reserved for company, and he’d like his wife to make some just for him, and not wait for someone she felt obliged to impress.