I had my first negative experience today at this location. It serves me right because just last week I was besmirching Costco. Anyhow, my wife and I were using self checkout when the machine flagged us for purchasing alcohol. Two associates who were flapping their gums clearly ignored us and following their conversation went their separate ways. After 5 minutes of standing there looking like idiots waiting for help I proceeded to try to cancel the order and walk out. My wife in a rare demonstration of charity decided to flag down an associate. Finally after about 10 minutes we were able to finish the checkout process.
My recommendation: take out self checkout if you're not going to oversee the lanes. Hopefully this is a blip in their service model in Gilbert's SAMS Club.