Same supermarket, same aisle, same jar of peanut butter. Last week it was $3.99. This week it is $6.49. Nothing about the jar changed on the way to Tuesday: same brand, same lid, same shelf. What changed is a number, and the strange part is not that it moved. The strange part is that nobody anywhere in the transaction, not the checkout, not the chain, not the label, will say what the jar cost. Not the price: the cost. What it took to make it, land it, and sit it on a shelf under lights. Ask, and you find there is no place where that number lives, or none you are allowed into.
It looks like a price problem
The obvious reading is that this is a price problem. Groceries are dear because two chains have carved the country up between them: Foodstuffs and Woolworths hold about 82% of the market (B2B News NZ 2025), and when the Commerce Commission studied the sector it concluded that “competition is not working well for consumers” (Commerce Commission 2022). On that reading the fix is more competition: a third player, a price war, a regulator with sharper teeth. Get the prices down.
There is truth in it. The concentration is real, the prices are high, and the loudest response the industry has managed is another loyalty card. But a dear market only explains $6.49. It does not explain why $6.49 was $3.99 the week before, and it does not explain why no number underneath either price is ever allowed out of the building.
$6 billion behind the shelf
Then the regulator went looking behind the shelf, and what it found was not a price. Four years after the market study, the Commission’s grocery monitoring flagged roughly $6 billion a year moving between suppliers and the major chains, payments equal to about 26% of the majors’ combined retail revenue, as part of what is holding grocery prices up (NewsWire NZ 2026). Hold the size of that against the till: for every $4 that crosses a checkout, about another $1 is moving in the layer behind it, in rebates and promotions and charges, shaping the shelf price from a ledger no shopper will ever read.
That finding rearranged the problem for me. I had been treating the missing number as something kept from shoppers, a secret held at the checkout, and the supplier-payments figure says the truth is stranger: the cost of the jar is not hidden so much as dissolved, spread across a web of payments that the regulator itself, with statutory information-gathering powers, is only now mapping. Opacity, it turns out, is not a symptom of the dear market. It is what keeps the market dear, because price can only be competed on where price can be seen.
Was, now, never
Think about what a special requires. A drop from $6.49 to $3.99 only reads as a bargain if you never learn what the jar costs to produce, and the whole apparatus of grocery marketing runs on exactly that ignorance. The price moves constantly. It dresses itself in was and now. It hides behind a membership card, among tens of thousands of lines no human could track. To comparison-shop, a person would have to carry a true number in their head and set it against the shop down the road, and every layer of the system is arranged so that no such number exists to carry. You can feel the design in the small tricks: the pack that shrinks while the price holds, the unit price printed in a font you crouch to read, in units that do not match the jar beside it, the special that is only special in the app. None of it is illegal, and none of it needs a conspiracy. It only requires that everyone, independently, declines to show their working. So competition, where it happens, happens on the appearance of value rather than on value: who stages the biggest percentage off, who has the shinier points scheme. You cannot comparison-shop a number you are never shown.
Show your working
What would break the fog is probably not a third chain competing on the same illegible terms, and probably not a regulator dragging one price down while ten thousand others drift. What breaks it is legibility. Print the working on the front of the jar, what it cost to land, what the seller took, the tax, and the theatre of specials and cards has nothing left to hide behind. The label stops being marketing and starts being a receipt.
Whether shoppers want a receipt is the honest open question, and I do not know the answer. It is possible that people prefer the small thrill of a bargain to the flat truth of a number, that the theatre is doing something for us that arithmetic would take away. A challenger that mattered would find out, because it would not really be competing on cheaper. It would be competing on being the only one willing to show its working, and discovering, at last, whether anyone was waiting to be told.