The difference is that Amazon said they don't use third party data to boost their own sales. In traditional retailers like Costco, if you are a product maker a

The difference is that Amazon said they don't use third party data to boost their own sales. In traditional retailers like Costco, if you are a product maker and supply Costco, you don't own any data from the sale of the product--Costco owns that data. In fact, you will have to pay for that data from data brokers (Retail Solutions Inc for example) if you want it.