Grocery investors are well aware of the overnight impact that Amazon.com, Inc. made in the market when it announced a buyout of Whole Foods Market, Inc. back in June. However, Amazon’s intrusion into the food business has been weighing on the food industry for much longer than a few weeks. News that Amazon will be directly competing with grocery stores hit stocks such as Kroger Co SUPERVALU INC. and Costco Wholesale Corporation like a sledge hammer. Costco shares are down 14.7 percent in the past month, Supervalu shares are down 20.0 percent and Kroger has tumbled 24.1 percent. But while grocery investors may just now be wising up to the threat that Amazon poses, other food investors have felt Amazon's sting for a while now. Amazon first debuted its private-label grocery business back in June 2016 when it launched its own brand of coffee, baby food, nuts, spices, tea, vitamins and other household items.Source