I shop Costco a lot.....but very little of it is food. Many of the products they sell are NOT less expensive than your local grocery store. You have to know your prices. Their meat is no bargain, but always excellent quality and same with their produce for quality.(although the produce is often a good price as well.)
I like their books and housewares and gifty stuff. I just ordered one of their clothes steamers.....the upright ones they use in clothing stores. Those things work so great. Mr. P.C. also gets the Costco Jeans and runners.