I go to Costco in either Windsor CA or Vancouver CA twice a year to get insulin. I don’t have a Costco membership.
Before I go, I have a friend with a Costco membership send me a Costco Gift/Cash Card online. The card arrives directly at my house through the mail, and I have to activate it with MY phone. I use the card to enter Costco, and at the cash register, a manager has to come and stick their key in so I can pay the difference between my cash card and purchase total with my debit card.