After doing hundreds of shops, it was on this particular sunglass shop that I got pegged for the first time. I did everything according to plan, then returned about an hour later. While the clerk is processing my return, he says, "I thought I'd see you back here." "Oh, really, why?" I say, coyly. "I thought you were a mystery shopper." I did the required, "What's a mystery shopper?" response, looking incredulously at him. He then began to tell me *in detail* all about the specific MSC and even told me their web site. He knew other companies that they shopped, how much they paid, etc. It was kind of amazing. Moral of the story, schedule your returns long enough after the initial shop to try to get a new associate, if possible. My scheduler said that this company's staff always try to spot the shopper.