Why the Same Product Costs Different Prices at Different Stores - The Hidden Logic of Pricing

Take a 500ml bottle of water as an example. The exact same product from the exact same manufacturer costs wildly different amounts depending on where you buy it.

Supermarket sale: 68 yen. Drugstore: 78 yen. Convenience store: 110 yen. Vending machine: 130 yen. Train station kiosk: 140 yen. Movie theater concession stand: 200 yen. Theme park: 250 yen.

The gap between the cheapest and most expensive is 3.7x. The water inside is identical. The explanation comes down to two factors: "location costs" and "the price of convenience." As covered in the true cost of bottled water, the water itself costs just 1-2 yen to produce. Everything else - the bottle, transportation, store rent, labor, and profit - accounts for the rest. Search "ミネラルウォーター" on Amazon

Supermarkets and drugstores keep prices low through a strategy called high-volume, low-margin selling. They accept a tiny profit on each item and make up for it by selling enormous quantities.

For example, if the profit on one bottle of water is 5 yen but the store sells 500 bottles a day, that's 2,500 yen in daily profit. A convenience store might earn 30 yen per bottle but sell only 50 a day, netting just 1,500 yen. The supermarket charges less per bottle yet earns more overall.

As explained in why drugstore groceries are cheap, drugstores deliberately sell food and beverages as loss leaders - products priced at or below cost to draw customers into the store, where they then buy higher-margin items like medicine and cosmetics. Behind every low price, there's always a reason it can be low.

Convenience stores and vending machines charge more because the cost of "convenience" is baked into the price. A convenience store stays open 24 hours and sits within a few minutes' walk of almost anywhere. Maintaining that accessibility requires late-night labor costs, premium rent near train stations, and frequent small-lot deliveries.

As discussed in the economics of vending machines, the price premium on a vending machine reflects the value of "right here, right now." When you're thirsty, do you walk 10 minutes to a supermarket to save 40 yen, or pay 130 yen at the machine in front of you? Most people choose the latter.

Movie theaters and theme parks charge the highest prices because they operate in a near-monopoly. You can't bring your own drinks into the theater - and that rule exists partly to protect the monopoly pricing. When there's no competition within arm's reach, the seller sets the price.

Once you understand that the same product costs different amounts at different stores, you can save money simply by being intentional about where you shop. Three rules cover the basics.

Rule 1: Buy planned purchases at supermarkets or drugstores. Build a habit of doing a weekly grocery run, and the savings over convenience store prices add up fast. If you buy 20 drinks a month, the gap between supermarket prices (68 yen) and convenience store prices (110 yen) is 840 yen per month - roughly 10,000 yen per year.

Rule 2: Carry a reusable bottle. Brew tea at home and bring it in a bottle, and your beverage cost drops to nearly zero. One tea bag (about 5 yen) makes 500ml of tea. Compared to 130 yen at a vending machine, that's a 125 yen saving every single time.

Rule 3: Minimize "emergency" purchases. Reserve convenience stores and vending machines for moments when you truly need something right now. A little advance preparation means you avoid paying the premium for instant access.

If you do end up at a convenience store, knowing convenience store markdown strategies helps you spot discounted items and keep spending in check.