The Issaquah Costco draws shoppers from across the eastern Eastside, including Bellevue, Sammamish, Factoria, Fall City, Snoqualmie, and North Bend. With shoppers pouring through a single warehouse from all those places, the aisles can clog fast.

The worst bottlenecks start when a cart is left dead center while its owner steps away for a sample or another item. In a store designed for bulk buying and oversized carts, that alone can turn an ordinary aisle into a traffic jam.

The fix is straightforward: keep carts to the side and leave room for others to pass through the aisle. The store may always feel crowded, but a little more aisle courtesy goes a long way when nearly everyone is trying to shop at the same time.

At a location this packed, a few feet of open space can separate a short grocery run from a slow shuffle from one end of the store to the other.