William Shakespeare wrote “The Tragedy of Hamlet, Prince of Denmark” (which, for obvious reasons, is typically referred to as just “Hamlet”) somewhere around 1600. And for centuries, the age-old philosophical question was, “To be, or not to be?” Had ol’ Willy been born in modern times, though, that question might instead have been, “To Costco, or to Sam’s Club?” Because if we’re being honest, that’s a far more important question, as it directly impacts our wallets on a near-every-day basis.

Most of us who visit these big-box stores are looking for a way to save money. When we leave pushing two carts full of stuff we didn’t know we needed in the first place, though, did we really save anything at all? Consumerist anxieties aside, believe it or not, both stores opened in 1983 and began the Costco versus Sam’s Club rivalry we still have today. They’re almost like a modern-day Hatfields and McCoy, but the preferred weapon of choice is bucks over bullets.

Technically, Sam’s Club (founded by Walmart’s Sam Walton) struck first, flinging open the doors to its first members-only store in Midwest City, Oklahoma, in April of 1983. Costco opened its first store in Seattle, Washington, just a few months later, in September of that same year. While both started in the same year, the story of these two economic juggernauts (and their rivalry isn’t that clean and simple.

A store called Price Club opened in 1976 in what had once been an airplane hangar on Morena Boulevard in San Diego, California. Founded by Sol Price and his son, Robert, it’s considered the world’s first membership warehouse club, and initially catered only to business customers in need of supplies and wholesale items. Jim Sinegal was the executive vice president of merchandising, distribution, and marketing for this lone warehouse store, which took off and thrived for several years.

In April 1983, Walmart’s Sam Walton launched his competing chain, Sam’s Club. Then, Jim Sinegal, taking what he had learned from Price Club, teamed up with Jeffrey Brotman to open the first Costco in September of the same year — and the big box store war truly began. A decade later, Sam’s Club was the dominant leader, raking in $14.7 billion annually at its roughly 400 stores. Second, with 94 stores, was Price Club, while Costco’s 103 stores placed it in third.

Realizing they wouldn’t be able to win the war by maintaining that status quo, Price Club merged with Costco in 1993, with the new enterprise relaunching as PriceCostco. The new company quickly generated $16 billion annually from 206 stores, edging out Sam’s Club, and eventually renamed itself Costco in 1997. Today, Sam’s Club and Costco are locked in a seemingly never-ending battle, with the two companies vying to offer the better deal on tires, televisions, and other goods to customers.