[goblin89]

> Stores know you want a pint of milk and loaf of bread.

You, me, perhaps: what about other buyers, many of whom don't come to the store with detailed checklists? Their experience involves a fair amount of in-store exploration. For them placing milk and loaf of bread far apart might arguably be beneficial, because it makes them go past all of that other stuff they may forget to buy otherwise. Indeed, I imagine such customers are also easier to upsell to and more prone to impulse purchases of products that yield better margins—and that's part of the shopping process they visit the store for. Alas, people seem to enjoy buying things.

In short, I wouldn't be so confident that a store with more ‘rational’ layout would score better in the eye of the customer, even all else equal.

Disclaimer: I don't work in this area of business and this is purely my speculation.