What's with all the tiny soda cans? And other grocery store mysteries, solved.

There's a behind the scenes industry that helps big brands decide questions like: How big should a bag of chips be? What's the right size for a bottle of shampoo? And yes, also: When should a company do a little shrinkflation?

From Cookie Monster to President Biden, everybody is complaining about shrinkflation these days. But when we asked the packaging and pricing experts, they told us that shrinkflation is just one move in a much larger, much weirder 4-D chess game.

The name of that game is "price pack architecture." This is the idea that you shouldn't just sell your product in one or two sizes. You should sell your product in a whole range of different sizes, at a whole range of different price points. Over the past 15 years, price pack architecture has completely changed how products are marketed and sold in the United States.

Today, we are going on a shopping cart ride-along with one of those price pack architects. She's going to pull back the curtain and show us why some products are getting larger while others are getting smaller, and tell us about the adorable little soda can that started it all.

By the end of the episode, you'll never look at a grocery store the same way again.

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