NEW YORK -- Bad news if you're mooching off of someone else's Costco membership: The retail giant is cracking down. When you enter Costco, you need to show your membership card to an employee to shop.

Sharing a credit card with a friend, partner, or family member may appear convenient, especially when managing common expenses. However, financial experts warn that this seemingly simple arrangement ...

Retail giant Costco is using a new method for cracking down on non-members who shop at their stores. In most cases, in order to enter a Costco, you have to show your membership card to an employee.

For years, many Costco shoppers quietly bent the rules—sharing membership cards with family, letting non-members tag along to checkout, or simply flashing a photo of the card on their phone. Now, that ...