I was in Trader Joes on Friday and asked one of the employees about a Spinach and Kale dip made with Greek yogurt that I loved and could no longer find. The shopper next to me said, “Ooohh, what was it called?” And so we chatted and she said, “Trader Joes has so many new products; the best way to find out what to try is to listen to what people ask for while in the store.” Yes, eavesdropping is...