We love Costco. Things we buy:
Dishwasher tabs (just got a BOGO 100+ tabs per container, for less than $12)
Garbage Bags (Kirkland brand...excellent).
Kirkland brand detergent (the BIG box of powder...works great, lasts forever).
Towels
Knock off uggs in the winter
DH's leather sneakers ($14.00). Last a long time! Comfortable.
Sweat socks...the kirkland brand is amazing...really high quality.
Coffee. Can't beat the prices anywhere.
Milk
Butter
Broccoli (frozen)
TIRES (three cars means we need one new set a year, and the savings here more than pays for membership).
Electronics, except for computers (I do not find their computer prices to be all that great), but on TVs they are wonderful.
Video games (if latest and greatest is your thing, the best price is here).
Small kitchen appliances
Swimsuits for the kids
Goggles for the kids
Spices of all sorts
Gosh, this list is really long. LOL! Seriously, I spend 1/2 my shopping dollars there, at least. I love the store and it's whole approach to doing business.
Rose