Maria Noyen/Business Insider
- Kirkland Signature, Costco's private-label brand, has won the company some die-hard fans.
- Nonfuel sales reached $56 billion last year, or nearly a quarter of Costco's annual revenue.
- One way the company tries to build trust? Each new item is approved by the CEO.
Costco is well-known for offering jumbo sizes and low prices on the leading national brands.
But some customers are even more enthusiastic about a brand they can only get from its warehouse club: Kirkland Signature.