Nice idea, but it nevertheless got me thinking. Just out of interest, what should a member of supermarket staff do if the person said, "Nope. Couldn't find the cat food anywhere"?
Should they:
a) say, "Oh, dear, what a shame. Better luck next time," or
b) say, "Hold on a mo, I'll just rush off and find you some. Which brand would you like?"
From my observations, they can either tell you which aisle it is on (so you or someone in your party can go get it) or use their microphone to call someone else up to the front so that that person can then go fetch what you need while the rest of your items are being scanned.
I have on occasion seen them leave the counter to go get the item (or check a price when an item inexplicably lacks a price or barcode), but when they do, they're quick because they know where it is.
Usually, though, I think a customer would ask one of the employees that patrols the aisles or stocks the shelves where to find something instead of waiting until they got to the counter.
