Cheerios used sampling to game Amazon’s ecommerce algorithms. During Amazon Prime Day (16th-17th June 2018), Cheerios offered a free family-size box of Honey Nut Cheerios to any Amazon shopper who spent more than $40 on Amazon Pantry. n addition to the box of cereal, customers received a $10 discount. But the transaction also automatically created a Cheerios shopping history for millions of Amazon Prime shoppers, infiltrating Amazon’s recommendation algorithm and moving Cheerios to number one in the cereal category, and even the number-one grocery item on Prime Day.