Munchie ranks 2020 in the pet registry with 49 male animals. It's a diminutive food-reference nickname — from munch, to chew enthusiastically — and belongs to the category of affectionate observation names that owners give animals who display a particular characteristic. Most dogs named Munchie are dogs who eat everything in sight.
The Behavioral Observation Name
Munchie is a name that tells a story about the animal's dominant personality trait. It implies a dog who treats mealtimes as his primary vocation, who has opinions about the food bowl's location, and who views all furniture as potential snacks. Labrador Retrievers, renowned for eating anything not bolted to the floor, are the stereotype, though Beagles' food motivation is equally legendary.
The Suffix Game
The -ie/-y suffix transforms Munch into something softer and more affectionate. Munchie reads warmer than Muncher, more playful than simply Munch. That softening suffix is doing considerable work here — it converts a behavioral description into a term of endearment. Compare with Biscuit and Pretzel for food names with a similar affectionate register.