Almost every supermarket places its most frequently bought items along the far wall. The layout is usually explained as a trick to force a long walk, which is part of it but not the main constraint.
Refrigeration has to sit against a back wall
Chilled and frozen cases need compressors, condensers and heat rejection, and that equipment lives in a plant room or on the roof at the rear of the building.
Running refrigerant lines the length of a store is expensive and inefficient, so the cases are placed as close to the plant as possible.
Dairy, meat and chilled goods therefore end up on the perimeter near the back, and that placement is largely fixed once the building is fitted out.
Deliveries arrive at the back too
The loading dock, cold store and preparation rooms occupy the rear of the building because that is where lorries can reach.
Perishables move from the dock to the shelf on the shortest possible path, since every minute out of temperature control shortens shelf life and raises the risk of loss.
Walk-in coolers are often loaded from behind the display case, so staff restock without crossing the sales floor at all.
The long walk is a genuine secondary effect
Once staples sit at the back, everything between the entrance and the milk gets exposure it would not otherwise receive.
Retailers use that, placing higher-margin and impulse-driven categories along the routes shoppers take on a short trip.
The effect is real, but it follows from an engineering decision rather than being the reason for it. A store built with plant at the front would lay out differently.
The front is reserved for produce and bakery
The entrance is given to produce, flowers and bakery because those categories set the impression of freshness that shapes how the rest of the store is judged.
They also need less mechanical support. Produce runs on misting and ambient displays, and bakery ovens are simpler to site than a refrigeration plant.
That combination makes the front the natural home for the categories that sell on appearance and smell.
What changes when the format shrinks
Convenience formats invert the pattern, putting chilled drinks and sandwiches near the door with a compact plant room behind a small back wall.
The trip is short, the basket is small and asking a shopper to walk would cost the sale rather than build it.
The contrast makes the logic visible: layout follows the length of the trip the format is built to serve, with the refrigeration engineering setting the limits.