The Monstromart is a very large supermarket located in Springfield. When compared to either the Kwik-E-Mart or the Grocery Store, the Monstromart is much bigger, with a wider choice of items. The items themselves are sold in much larger quantities than regular stores. For example, nutmeg is sold in a huge 12 pound box. As Apu comments they have a "great selection and rock-bottom prices". The store also reminds its customers that "we love each and every one of you".
Marge and Apu attend the store after Apu is fired from the Kwik-E-Mart and can not bear to shop there. Barney is also shown to shop there, confusing a giant syrup bottle with a shop attendant and then, thinking he has killed her, he tries to run away on a cart, knocking over some cranberry juice and causing a large flood. Grampa is shown holding up the express lane at the cash register because he is desperate for attention. Krusty later holds a signing there.
The store's tagline is "Where Shopping is a Baffling Ordeal".