Costco is one of America’smost popular and successful grocery retailers, but it’s not your typical grocery store.

It’s a club.

You mustpay a yearly feein order to shop there.

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And, like any club, there arerulesthat you should probably follow.

You are also entitled to various other perks, as well.

But, if you break the rulesor, even appear tothen you’re bound for trouble.

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You may even lose your precious membership altogether.

At least one alleged offender reportedlygot bootedfrom the premises recently.

Don’t let this happen to you.

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ensure your next Costco run goes as smoothly as possible by following these essential rules.

Your membership card is proof that you belong.

Ideally, it will feature an up-to-date photo of you on the back (more on that below).

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Costco simply will not accept payment without first scanning that all-important card.

If you are the forgetful sort, there is a backup in case you ever leave your card behind.

Download the Costco mobile app.

Costco membership

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you’re able to upload a digital version of your membership card and have it ready to go.

While the app itself islacking in many areas, the digital membership card is a major perk.

It’s not a perfect substitute for the actual, physical card, however.

Not your spouse or significant other.

And definitely not that random dude standing behind you in line who claims that he left his at home.

Card sharing is strictly prohibited, as many shoppers recently found out the card hard way.

“They took the card away.”

Employees are now regularly checking photos to verify that your face matches the image on the card.

Some shoppers saytheir very identities have been called into question.

“We don’t feel it’s right that non-members receive the same benefits and pricing as our members.

“Only Costco members may purchase items,” according to the rules.

“This happens a lot at my Costco,“one customer wroteon Reddit.

“I have a membership and my husband wants to pay with his credit card.

They do not allow that!”

Getting caught with someone else’s credit card can really delay your checkout time.

But it seems even this legendarily accepting club has its limits.

Turns out, there were many.