Gordon Food Service - There is now one near me.
We have one in Peoria, and I love it! No membership card...open to the public. It is primarily a restaurant supply store, though. Doesn't really compare with Sam's. Most of the items are their own brand. About 1/3 of the inventory is strictly stuff a restaurant would use...styrofoam cups, pizza boxes, etc. I do get my parchment pan liners there for a great price.
Food is packaged in large sizes, but very reasonably priced. Their deli roast beef is very tasty, and their frozen fruits and vegetables are very high quality. They also carry Minor's soup bases, which I can't find anywhere else in my area. Not sure how I'd live without the chicken one!
It's also a great place to shop if you're doing fundraisers for your church or school....big boxes of name-brand candy bars, etc.