6 myths about Costco that aren't true, according to members who shop there weekly

According to David and Susan, a popular Costco myth is that the retailer doesn't sell items from local brands. The couple said they've often spoken to people who think only products made by huge manufacturers or Costco's signature brand, Kirkland, are sold in the store.

But, according to the couple, that's not the case. While accompanying BI on a recent tour of Costco's warehouse in Brooklyn, the couple pointed out several products — including Rao's marinara sauce — made by smaller businesses and sold in Costco locations worldwide.

Costco warehouses generally look the same no matter where you shop, but that isn't the case when it comes to products, David and Susan said.

According to the couple, items sold at Costco, especially those in the grocery aisles, depend massively on the location and the demographic of the surrounding population.

"Regionally, about 40% of the product is different," Susan said.

The couple has visited over 200 Costcos worldwide, and they said they've come across plenty of unique delicacies sold exclusively in certain areas.

"In Alaska, you get reindeer sausage, and in Taiwan, the rotisserie chicken is sold with its head," Susan said as an example. "Each warehouse has only 3,800 items, and it's highly, highly curated."

Susan and David aren't the only ones to notice differences between Costco stores depending on the region.

Business Insider reporters Joey Hadden and Talia Lakritz previously visited locations in Canada and Iceland. They both saw an array of items not sold in the US, such as maple leaf cookies, Hungarian beef sausage, dried fish fillets, and Icelandic yogurt.

Indeed, some Costco products — especially pantry staples like rice and oil — are sold in huge quantities.

But not everything has to be purchased in bulk, David and Susan said.

"People think of Costco as a big-bulk retailer," David said, adding that it's a total misconception.

"Not everything at Costco is super-sized," Susan said in agreement. For example, the pair referenced a jar of avocado-oil mayonnaise that they're huge fans of.

"It's a regular-sized mayonnaise jar. It's a great price, so it's a myth that everything's huge," she added.

According to David and Susan, those less familiar with Costco often think that members of the wholesaler either have large families, large houses, or both.

But the couple, who shop at Costco weekly and live in a "tiny" 450-square-foot apartment in Manhattan, say they are living proof that isn't the case.

"People have this misconception that you need to have a huge house or a huge home to shop at Costco," Susan said. "It's just not true. We're proof of it."

If you've ever shopped at the same Costco more than once, you'll notice that the shelves are constantly changing. New items are rotated in while others are discontinued at the same time that staples are shifted around.

This is what's known as Costco's "treasure hunt" design layout, which can be perceived as a merchandise strategy to make shoppers stay at Costco longer and buy more in the process.

But David and Susan don't think that's why Costco switches things up so often.

"People say, really obnoxiously, it's to trick you into buying stuff. It's not. It's just to keep it interesting and fun," Susan said.

The average size of a Costco warehouse is 147,000 square feet, so the idea of popping in for a quick shop in under 30 minutes sounds impossible — but it isn't.

"To do that, you need to know what you're really looking for. You need to be disciplined," David said.

Although it might be possible to get what you need quickly, the couple said that the approach slightly defeats the purpose of going to Costco in the first place.

"The problem is that you're going to miss really good bargains. You're going to miss special items. You're going to miss a lot of stuff," David said.