Shop at Costco for free, no membership required !
If you rarely go to Costco, and/or know a Costco member / friend who will buy a few $10 Costco 'CashCard' aka gift cards for you, you don't need a membership. Use ONE card for each visit.
Just enter & pay using the gift card. The first $10 of your purchase will have to be paid from the gift card, the rest can be paid via credit card, debit card or cash.
I've done this for 5-10 years, never had a problem. Even with returns and discounts/sale prices.