It’s subtle, but stores that offer the smaller carts usually have higher prices. Warehouse stores that offer the large carts serve a purpose for bulk loading. When you enter a store and see that the little cart is the only option then walk away. Smaller carts are easier to push but you can’t put as much in them, so the store will jack up their prices so that you can’t carry too many of their items to your home. I’ve noticed these carts at Whole Foods, Trader Joe’s, Harris Teeter, and now PetSmart.