Exterior of a Costco store
Here's Why Costco Fans Shouldn't Stick To Their Closest Location
Because individual branch managers are the ones who set discounts and choose stock based on demand at Costco, it's worth shopping at different locations.
Not all locations are the same size, either. Bigger stores can provide access to a wider range of unique items at better prices, which are based on demand and popularity.
You could just shop online, but using this strategy means you'll get hit with shipping costs. Instead, visit as many locations in person as you realistically can.