You buy too much produce. Costco has plenty of items that you can buy in bulk, from crackers and bread to canned drinks and pantry staples. But you can also buy plenty of fresh produce in bulk as well.
You buy name brands. When it comes time to make a purchase, those well-known brands could also set you back a lot of money.
You try items and find out you don't like them. You could be contemplating the money you spent by purchasing something in bulk while starring at a bulk version of something you can't even imagine eating.
You have the wrong membership card. Costco has two types of membership cards: Gold Star and Executive. If you spend a lot of money at Costco, it may be worth it to upgrade to an Executive membership
You wander the aisles. Costco is large and challenging to navigate, like any warehouse shop. Additionally, it is well-stocked with a variety of things, including food, home goods, and clothing.
You shop when you're hungry. Costco has a lot of delicious food samples, but it's important to resist the temptation to shop when you're hungry.
You don't return things. Costco has a generous return policy, so don't be afraid to return things that you don't like or don't need. You can return almost anything, even if you've opened it, as long as you have your receipt.