Ron, that depends on how you define "enough." What is "enough" for a single person still living at home may not be "enough" for a single mom on her own with 2 kids.

Also keep in mind that Costco charges a pretty hefty membership fee. In Tennessee it was $49 last time I checked, whereas Sam's is $30. I doubt that many people who shop at Wal-Mart regularly have $49 for a wholesale club membership. I don't think it's any coincidence that the Costco in the Nashville area is in Williamson County, which has been the wealthiest county in Tennessee since before the Civil War.