How much did donuts cost when this phrase became vogue? Cuz now they cost a dollar, at any bakery chain, with a slight discount for multiples. Sort of defeating the purpose of the phrase.
Probably a dime or less.
During the Depression they were less than a nickel.
I would take the donuts, or doughnuts for our British friends. Cut out the middle man.
Growing up, we used to call them “dog nuts.”
When I was in the Navy, we called them “fat pills.” 
In Cleveland we called them “Spud Nuts”.