Who said TV can't teach us anything?
If you watched Grey's Anatomy over the past few seasons, then you were probably introduced to their "patient care" dummy, Stan, commanded by the chief in one episode. The goal was to deal with a frustrating patient -- one who wasn't effectively describing his symptoms -- and to provide a diagnosis while keeping the patient calm. It may have just seemed like a learning opportunity turned prank on the show, but it was actually a lesson in how mystery shopping can be used in medicine.
Mystery shopping is most often associated with retail and often takes a creative mind to envision it branching out to other industries. It is not just businesses selling a specific product that can learn from the experiences of their customers; it's any industry that is selling a service that relies on returning customers.