Green’s Dictionary of Slang

munchie n.2

(Irish) a derog. term for a country person.

Fortnight issue 141-72 39/2: ‘Somebody from the country . . . a munchie’ ‘Mary is no munchie’.
[Ire]G. Coughlan Everyday Eng. and Sl. [Internet] Munchie (n): Somebody who lives in the country.