Costco is cracking down on card sharing so that only members can take advantage of the savings.

Employees will now be stationed at self-checkout lines to check member identification cards.

Costco says nonmembers should not get the same benefits as card holders.

In addition, they say membership fees play a big role in the warehouse club being able to offer low prices.

Posts on social media show some Costco shoppers complaining that employees are asking for ID cards again at the checkout line.

Costco management released a statement saying, "Costco’s membership policy has not changed. We have always asked for membership cards at our registers at time of checkout. Our membership policy states that our membership cards are not transferable and since expanding our self-service checkout, we’ve noticed that non-member shoppers have been using membership cards that do not belong to them. We don’t feel it’s right that non-members receive the same benefits and pricing as our members. As we already ask for the membership card at checkout, we are now asking to see their membership card with their photo at our self-service checkout registers. If their membership card does not have a photo, then we ask for a photo ID."