If you’re a frequent customer of Kroger grocery stores who has, at one time or another, used the store’s self-checkout, you may want to double-check that you haven’t been scammed. Police in Elkins, West Virginia, warned the customers of the local Kroger’s location that they had discovered a scamming device hidden in the self-checkout kiosks this week, according to a Monday report from The U.S. Sun. The device found is known as a skimmer. Scammers can place the skimmer right over a checkout station’s card reader without anyone knowing. When customers swipe their cards through the skimmer — thi…