I love Costco. Great prices, decent customer service, great lunch deals! Where else can you have a 1/4 pound hot dog and a drink for $1.60? Of course they have free samples that encourage you to buy an item. They sometimes hook me with those. But you can have lunch every day in that place and never spend a penny. And like Elle said, the items are a much higher quality than Sams Club.
If you didn't know, Costco is a warehouse club that sells things in bulk. Then also have jewelry and electronics that are a great deal. I often order items from the web-site when I can get free shipping. Also note that they have great prices on tires (often beating Discount Tire) and gasoline. The pumps are a little hidden on the east side of the building, but they have plenty of them. No diesel though.
The only downside to this Costco is the parking. Holy shit! There have been many times when I've wanted to go postal on the morons who are parking their 25 foot long SUV's in tiny assed spaces blocking the entire aisle for 10 minutes while they lube up the sides to squeeze in. All this while they yap on the phone and adjust their tits/nuts. But then, I'm impatient. I usually park on the side lot south of the tire shop.