Brands tap into the "buy in bulk" ideology that couponers love. Consumers believe when you buy more than you need at the moment, it will pay off in the long run. But the truth is that you rarely break even. Most times, you end up with too much of one item and only use a fraction of it while the rest spoils. Bulk buying can even lead to hoarding-like tendencies, unhealthy eating habits, and ultimately, an empty wallet, according to Dholakia.
"They spend more because they end up buying items they don't really need just because they are on sale, or buying more of an item because of how the promotion is structured," Dholakia told Business Insider. "This is quite common in grocery product categories but also occurs in other categories like fashion."