I have never heard of Dave Ramsey, so I can't respond to anything specifically about him.

As for Costco, I find it to be an outstanding place to stock up on wine. The bottles are the same size as the ones you get anywhere else, so there is never an issue about buying more than I need.

Other items I commonly get at Costco: organic fruit, organic vegetables, vegetable buillion, shampoo, razor blades.