You can join the members club when checking out for free.
They have a membership program that anyone can join. You get benefits, but you must bring your card.
C Y, you are asking the Google Community, made up of people like you...not the store itself. So, answers may not be as accurate as if you called the store and asked them. That said, typically, "members only" usually refers to a special price or discount available to nembers of the store's club. Non-club members pay the regular price. As Jeff said, you can join the club at the register for free.
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