While bulk pricing is legal, distributors are legally mandated to provide the same pricing models to all qualified customers. However, the US hasn’t enforced these laws in a long time. Theoretically Walmart and Mom and Pop’s Grocery should be able to place the same size order for the same price but many big box stores started bullying the distributors for special secret pricing and then forbade them from offering those prices to anyone else.
But not old enough to remember that charges were eventually dropped?