I LOVE COSTCO, but I try not to go often because it's usually packed with people and the checkout lines are excruciatingly long. It just feels a bit crowded and chaotic.
My main purpose of shopping at Costco is to stock up on grocery items. Costco has high quality food at reasonable prices. They have a good selection of organic products. I like to buy meat at Costco because they have antibiotic/hormone-free options. The produce is always high quality. They have cage-free eggs. They also have a good selection of wine/beer/liquor. I was skeptical at first, but Kirkland brand liquor is actually really good and comparable to top shelf brands...at a fraction of the price.
After shopping around, I recently purchased a TV from Costco and it cost $150 less at Costco then anywhere else (Walmart, Target, Best Buy, Amazon, etc.)
They really do have some great deals, so I'll keep braving the crowds to get my Costco fix.