Is buying in bulk actually cheaper?
Sometimes. The larger package only wins if its unit price is lower and you actually use what you buy before waste, spoilage or storage costs eat the savings.
What you need to know
Bulk packaging looks cheaper because the total package is bigger, but the useful comparison is the unit price: cost per ounce, pound, liter or item. A larger package can have a lower unit price, but not always. Promotions can make a smaller size cheaper per unit, and food that spoils before you use it turns a paper saving into a real loss. The practical test is simple: compare unit prices, estimate how much you will actually use, and include membership, storage and waste in the decision.
Unit price, not package price
How much you can realistically use or store
A larger package is not automatically the lowest unit cost