Several months ago I made a spreadsheet and did some price comparisons between Wal-Mart and Sam's. The membership to Sam's is $40 a year so you really have to do your homework to find out if it's a better deal for your family.
It's hard to make blanket statements about what is cheaper at Sam's. If you are willing to buy generic and if you coupon, then Sam's may not be cheaper. The things I have listed though (I'm pretty sure) are way cheaper at Sam's vs. even the generic pricing at WM.
Shredded Cheese, Peanut Butter, Vanilla, Chocolate Chips, Toilet Paper, Trash Bags, & Hand Soap are all pretty universal shopping things that are significantly cheaper at Sam's.
These things alone have made our membership worthwhile. I have been going to Sam's every other month. We also stock up on fresh fruits and veggies when we go, they are the best. You can get a big bag of cut up Romaine lettuce for under $3!
I also buy a HUGE $22.00 bag of Tyson boneless, skinless chicken breasts when we go to Sam's. Kroger sells it cheaper when it is on sale, but I love the big bag. The pieces are not gargantu like you get in the store. It is, in my opinion, 10 pounds of good lookin' chicken.
I'll tell you one thing I found when I was price comparing. That Wal-Mart is tricky. The marketing people are good. Did you know that Daisy sour cream is the same price (or cheaper) than the Great Value brand? You've got to watch.
You'd think the generic is automatically cheaper. It's not always so pay attention to that.
When price comparing, I realized what a creature of habit I am. The fresh spinach really threw me for a loop. There is one brand I always buy. After looking at all the options I found out there was a bag that was way, way, way cheaper. It was at the very bottom of the shelf so I had never noticed it.
Do you think in some crazy ploy to make more money they'd put more expensive food at eye level? You bet they would!
Here's another thing. Raisin Bran cereal. Kellogg's is on one side of the aisle, Post is on the other. The Post brand is a lot cheaper. But you have to know to look on the other side of the aisle for it.
Other things I've been purchasing from Sam's...Parmesan, Refried Beans, Pinto Beans, Corn, Laundry Soap, Downy, Gum, Cereal, Little Smokies, Sausage, Coffee, Tea, Bread, Chips, Water Bottles. And of course an $ .86 Pibb Extra for the shopping trip!