The praxeological view. Let us say it from the outset: the position of this note is not a popular one. Anyone who fills a shopping basket every week sees the bill growing, and a shelf 6.5% cheaper feels like a breather. That pressure is real, and the wish for relief entirely understandable. That is exactly why it is worth examining calmly, step by step, whether a cap on the profit margin gives that relief or merely moves it elsewhere.

What a price is. A price is not a number the merchant picks at will. It is information: it condenses how scarce a good is and how much it costs to bring it to the shelf, from the field and the factory to transport, the electricity for the refrigerator, and the cashier’s wage. When the price of olive oil rises, it tells the buyer “economize” and the producer and the importer “bring more.” A cap erases part of that message.

What a cap on the margin does. The margin is the difference between what the store pays the supplier and what it collects from us. Out of it come rent, electricity, staff, and spoilage, and whatever is left over is the profit. If the state decrees that on a given product code this margin may not exceed a limit, that code becomes less attractive to keep on the shelf than another one without a cap. The cap is a form of price control, a triangular intervention, as Murray N. Rothbard calls it: the state steps in between buyer and seller and sets the terms of their exchange. The consequences are well known and predictable:

1. Fewer product codes. When a product no longer leaves a profit, the first thing a merchant does is promote it less or withdraw it. The list falls from 1,790 to about 1,000 codes. Part of the drop is explained by the 450 school supplies, which were seasonal; even without them, however, the codes shrink from about 1,340 to about 1,000. The reports do not say why, and theory alone is not enough to prove it. But the drop is exactly what one would expect: the less a code pays, the fewer are left willing to keep it cheap.

2. Smaller packages, lower quality. If the price cannot follow the cost, the product itself can adjust: 450 grams instead of 500, less cocoa in the chocolate, cheaper packaging material. The receipt shows the same price, but the basket holds less.

3. The cost shifts. The store’s rent and electricity have to be paid. Whatever is not covered by the capped codes tends to be shifted onto the codes without a cap. Ludwig von Mises describes this in Planned Chaos:

“If some branches of production were left free, the result would be a shifting of capital and labour to them and a corresponding fall of the supply of the goods whose prices the government had fixed.”

4. Less supply, queues, and shortages. Whoever already works on the thinnest margins—the small neighborhood supermarket, the small producer, the importer of a specialized product—is the marginal producer: the first to withdraw. Rothbard explains that the shortage is not the cause of the control but its result:

“For the truth is the reverse: price control creates an artificial shortage of the product, which continues as long as the control is in existence—in fact, becomes ever worse as resources have time to shift to other products. If the government were really worried about the short supply of certain products, it would go out of its way not to impose maximum price controls upon them.”

A cap on the margin has a less visible side effect too. If the limit is a percentage on the purchase cost, then the more expensively the store buys, the more euros it is allowed to earn. One of the market’s most useful incentives is thereby lost: bargaining hard with the supplier, so as to sell more cheaply than your competitor.

Who pays. The bill does not vanish; it is shared out differently. It is paid by whoever buys the products that are not on the list, whoever no longer finds on the shelf the product he wanted, whoever gets a smaller package at the same price, the small merchant who cannot afford to sell without profit, and the taxpayer, who pays for the Authority, the inspections, and the complaints app. This is the opportunity cost of the measure, printed on no receipt.

Why the margin is not the cause. The price on the shelf is the last link in a long chain. Before it come the higher-order goods: fertilizers, fuel, electricity, raw materials, transport. According to ELSTAT, Greece’s statistical authority, producer prices in industry rose 20.4% year on year in September, mainly because of energy (+41.2%) (Economico Markets, November 2). The minister himself admits that energy “multiplies costs.” If cost is rising at the start of the chain, controlling the margin at its end is like a doctor who brings down the mercury in the thermometer instead of the fever. And behind the general rise in prices lies something deeper even than the wars: inflation in the Austrian sense, that is, the increase in the quantity of money and credit expansion by the central banks and the banking system. When more euros chase the same goods, the purchasing power of each euro falls. Rothbard notes in the same chapter that general price maxima are usually imposed for the purpose of “preventing inflation,” “invariably while the government is inflating the money supply by a large amount.”

What history shows. In AD 301 the emperor Diocletian issued the Edict on Maximum Prices, with limits on hundreds of goods and the death penalty for offenders, at a time when the currency had already been heavily debased. His contemporary Lactantius writes that goods disappeared from the market and that the edict was eventually abandoned. In 1971 U.S. President Richard Nixon froze prices and wages to hold down inflation. In the years that followed, the controls were accompanied by empty meat counters and, with the controls on fuel, by the well-known lines at gas stations in 1973–1974. Place, era, and currency change, but the logic stays the same: when the price is not allowed to tell the truth about cost, the empty shelf and the queue tell it instead.

What would really help. If the goal is a cheaper basket, the way is to lower the cost, not to forbid it from showing.

• More competition. Whatever makes it hard to open a new store, for a new importer to enter the market, or for a producer to sell directly—permits, bureaucracy, regulations—keeps margins high. The competitor who sells more cheaply squeezes margins more effectively than any cap, and without emptying the shelves.

• Fewer taxes along the chain. VAT falls on every price, and the excise duty on fuel on every truck that carries food. The government itself, according to the minister, is asking Brussels for room to cut “possibly taxes concerning fuel.” That would lower costs along the whole chain, without anyone deciding from above which product is “entitled” to be cheap.

• Sound money. As long as money is produced at will, prices will keep rising, and every government will look for someone “greedy” to blame. Money that cannot be multiplied by a committee is the only lasting protection for the purchasing power of those who live on a wage or a pension.

The wish for a cheaper basket is a fair one. The question is whether we serve it by hiding the cost or by lowering it. The cap does the first. The free market, with competition, lower taxes, and sound money, does the second.