Oh Costco is my happy place, especially since I moved down south and it's not a traumatic experience anymore
The things that I pick up on a regular basis are:
Tequila lime chicken wings (frozen)
Precooked chicken meatballs
Chicken burgers
Frozen turkey burgers
Big packages of chop meat (hubby prefers to patty his own burgers and freeze them)
Smoked gouda
Brie
Muenster slices
Blue cheese
Queso fresco
Marinated mozzarella balls
Citterio rosemary ham
Rotisserie chicken
Bacon crumbles
Chicken thighs in tear apart packages of 5 that are easy to pop in the freezer
Steaks
Butter
Sour cream
Heavy cream & half n half
Bags of shredded Colby Jack
Detour protein bars
Beer brats
Kielbasa
Pecans
Almonds
Pistachios
Eggs
And so much more. I really find it cost effective to buy most of this stuff there and we use a lot of it quite quickly, and freeze quite a bit in individual meal portions too