What must be done before processing a supply purchase transaction at Costco?

Scanning the supply membership card is essential before processing a supply purchase transaction at Costco because it ensures that the customer is a valid member entitled to make purchases. Costco operates on a membership model, and this requirement helps maintain the integrity of the membership system while also providing a clear record of transactions linked to individual members. This step not only confirms that the shopper has paid for the privilege of shopping at Costco but also allows the company to track sales and inventory more effectively.

Validating customer identity or requiring manager approval is not standard procedure for every supply purchase, as membership status is usually sufficient for transactions. Checking for expired items is more relevant during the inventory management process rather than being a prerequisite for processing a supply transaction. Thus, scanning the supply membership card is a foundational step in the transaction process at Costco, highlighting the importance of membership in their business model.