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10 Things Your Grocer Doesn't Want You to Know

"Specials" Make You Spend More

Five for $10! Buy three, get two free! What a deal, right? Not always.

Studies show that when shoppers see numbers in a sign, they're likely to buy 30 to 105 percent more of that product. That's because if we think we're getting a deal, we tend to purchase more. Signs that say things like "limit 10 per shopper" are like catnip to us, too. We'll buy 10, even if we don't need 10. And that's not really a bargain, is it?

Research also tells us that when we shop, we usually buy one or two of the same product at a time. That's our limit. But when an in-store promotion throws numbers at us and suggests we buy more -- "so you don't run out!" -- we'll actually readjust our usual limit and buy more.

The psychology of shopping -- pretty interesting.