Because Costco is not universally cheaper. Costco discounts a few categories of products to lure you to shop there, but has higher prices in other categories. Fresh produce, meats, milk, and cereals cost more at Costco. Bulk packaged foods, frozen foods, and bulk household items are usually cheaper.

A lot of people don't notice this, and buy everything from Costco for the convenience, when it may be cheaper elsewhere.

For me personally, if I'm buying a large amount of meat, I buy from my local grocery store, as it's significantly cheaper.

That's not at all my experience for produce. It is extremely price-competitive. And many Costco produce items are best-in-class IMO. I haven't found better pomegranates, avocados, or blueberries anywhere else.

You can maybe find some meats cheaper elsewhere if you're shopping sales or buying a whole cow from a farmer. But chicken, turkey, or seafood? No way. And also consistently all high quality.

> For me personally, if I'm buying a large amount of meat, I buy from my local grocery store, as it's significantly cheaper.

Perhaps this is regionally dependent, but not only is the meat cheaper at Costco for me, but it is also higher quality. You do have to buy much more of it at a time, but that’s not really a huge issue in my view.

This hasn't held true for me (in SFBA). Virtually everything in the grocery aisle's between 0% and 50% cheaper than the next best option.

Meats do not cost more at Costco. Costco meat is cheaper and often is the only place around that has higher quality grades of beef.