That grande latte on the way to Target may be doing more than waking you up. According to the study, ‘Caffeine’s Effects on Consumer Spending,’ published in the Journal of Marketing by Dipayan Biswas of the University of South Florida and eight co-authors, people who drink a caffeinated beverage before shopping end up buying more items and spending more money than people who don't.
The team conducted a few experiments, three in real retail stores in France and Spain, and two in lab settings with university students in France and the US. The pattern, they found out, was the same in every case.
What the researchers actually did
The Journal of Marketing study was not a survey that asked people to guess how they would behave. In an experiment in France, roughly 500 shoppers entering a home-goods store were offered either caffeinated or decaffeinated 50 mL espresso before shopping. The caffeinated drink contained about 100 mg of caffeine, and staff checked their receipts as they left.
On an average, coffee drinkers bought 2.16 items for about 27 euros, compared to the decaf group, which bought 1.45 items for about 15 euros. In a second experiment, shoppers at a department store in Spain were served coffee or plain water, and then sent off on a two-hour shopping trip. The coffee group averaged nearly 70 euros, versus around 40 euros for the water group.
