I thought that too, and did my first shopping there this month, my wife bought the card because the contacts she needed to get were cheaper than the cost of the membership )seriously).
I went there haloween and spent 420 dollars and have saved almost three hundred off my grocery bill in the last month. It's pretty wild, you just make one trip to the market instead of four and its close to 40 percent on the dollar off and things you use regularly, like paper towels and cereal, dog food, stuff like that. Two pounds of coffee for 12 bucks/ 24 rolls of paper towels for 11 dollars.
The years membership is like 50 bucks.
It took me a while to figure it out, and we have a tiny place especially in the kitchen, so I know it works well.