Costco

Coffee, eggs, yogurt. Here in CA, they have organic hardboiled eggs. They're actually cheaper than raw organic eggs. I feel guilty about the extra packaging but they're nice to have around.

I get avocado, olive & coconut oils; lots of cheeses; some veg; organic meats & eggs; clover organic milk; pastured butter; bulk protein bars & organic school lunch snacks; wine; household items; grain free cat food; and virtually all of my workout clothes at Costco!

I have 4 children so I could be there every week practically! However, like many have suggested... I say in terms of prices... frozen fruit, fresh spinach, nuts, eggs and all the non food items such as paper products like kleenex, tp and paper towels are worth it.

AVOCADOS!
Peet's whole bean coffee
TP/Paper towels/Napkins
Meats
Breads
Cheeses
Apples
Pet food
Butter
Rotisserie chicken - theirs is the best in my opinion, and you get a nice big, tasty bird with lots of meat on it for five bucks. I can feed my family 3-4 meals on one bird.
And their premixed Golden Margarita is great - I love taking a bottle on camping trips, or just keeping one in the fridge - nice and easy on a Friday night!

Canadian as well. I typically go to Costco for produce. You can't beat their prices on produce. They also have big packs of beef jerkey, and also 12-packs of Naan bread that I use to make mini pizzas. They also usually have great prices on yogurt (greek and normal)

Apple raw ( package of seven)
Old fashioned Quaker rolled oats ( not instant). Package of 10 pounds
Organic eggs
Greek Yogurt plain (Costco Kirkland house brand)
Cottage cheese
Pecorino romano cheese wedge
Jalsberg cheese wedge
Green Tea (Matcha and Oolong)
Seasonal raw fruit ( Blueberries, strawberries, peaches, clementines, etc)

I love Costco usually buy my meat there then separate into what size I need being empty nesters. Don't buy a lot of fruit produce don't eat it fast enough buy broccoli and celery, chicken breast not frozen (too much salt) butter, eggs, some bread laundry soap etc. I also have an app on my phone called Flipp which you can set up with your favorite stores then type in search what your looking for and it will list it at which store who has it cheaper if your a shopper who doesn't mind going from store to store. I use it for
Produce cause here in Canada it's crazy.

There are ultra discount stores in my neighbourhood that I frequent for regular foods, like Giant Tiger, No Frills, and H & W Produce.

Since I am feeding for two, I NEVER get bulk spices from Costco any more. I won't use them up.

Costco is great for unique bulk items like Edamame, protein bars and protein powder. They have a black bean pasta worth trying, and a wafer-thin flat bread. Their snack tuna tins are great.

I am a Western Canadian, so my store availability and food choices might be different than yours.

My favorite's are the Kirkland brand Cashews, better then Planters or any other brand.
Persian Salads, again yum.

skinnypop
string cheese
block of cheddar cheese
chobani
fruit
all natural peanut butter
cheerios
toilet paper
bread
dog food
kirkland moisture shampoo and conditioner
gillette floss
beans/chili

ugh i love costco. there's a lot of good stuff that i know i'm missing on my list.

Part two, inspired by rereading:
Kirkland Greek yogurt in the large tubs, which I dish out into small Rubbermaid containers along with the aforementioned Three Berries to make my own fruit-on-bottom yogurts with far less sugar.
Kirkland brand peanut butter *rocks.* Two giant jars for somewhere around ten bucks, and it's all-natural without feeling the need to be labelled as such. No added sugar or oils or ANYthing. Just peanuts and a bit of sea salt. All this means is that it will separate, but stirring (or storing it in the fridge) takes care of that.
Canned beans, found in the same aisle as the soup.
Craisins. Almonds and/or walnuts from the baking-stuff aisle not the snack aisle so there's no salt added, but I have a hard time finishing those before they start to go stale (even with storing inside airtight containers) so I don't get them all the time.

Don't forget about Costco online too! Got my elliptical and fitness band online!

I noticed last night my Costco now has calories listed on the food court menu board. I don't know how right they are. It said the pepperoni pizza had fewer calories than the combo or cheese slice. I guess it's possible. A churro is over 500, I think. Yikes.