Let's say you're in a rush after buying a fan at Costco. You look past the line packed with people and carts and spy a lone employee standing by the exit. Do you walk over and show your receipt? What's the worst that could happen? Let's ask Reader Shay. “ On June 23, 2010 at the [redacted] Costco Center at around 11am I made a quick stop in to return a couple items and to pick a fan. Both the returns process and the checkout went wonderfully as usual. It only took me 2 minutes to get in line and...