May 16, 2026 – 5.00amThirty-five years ago, at an unnamed university in the American south-west, researchers invited 150 undergraduates into a laboratory to do a bit of shopping. Unlike a normal lab, this one had been converted into a supermarket. Products were arranged on shelves, shopping baskets were borrowed from a local grocer. Toothpaste, peanut butter and toilet paper, scientists wrote, “received the promotion manipulations”.That research ultimately found some shoppers would react to promotional announcements – words like “everyday lowest prices” – without any evidence there had been a real reduction in prices at all.Subscribe to gift this articleGift 5 articles to anyone you choose each month when you subscribe.Subscribe nowAlready a subscriber? Carrie LaFrenzSenior reporterCarrie LaFrenz is a senior journalist covering retail/consumer goods. She previously covered healthcare/biotech. Carrie has won multiple awards for her journalism including financial journalist of the year from The National Press Club.Kylar LoussikianDeputy editor – businessKylar Loussikian is the Financial Review’s deputy editor – business.Fetching latest articles