Supermarkets regularly send fake shoppers through the store to see how everything's going. There's probably a term for it in the trade.
Corporate should be checking to see if the NY Times #1 bestseller is prominently displayed at every bookstore, and not hidden in the back.
Secret shoppers...not a bad idea. Unfortunately, not necessarily always effective. If each store is open 10 hours a day and has 10 employees working the entire day, that is potential 100 hours of "face time" with customers per store. It only takes one or two minutes of one "bad seed" employee to do what was discussed on the bordersunion website. I liken it to what President Bush or Secretary Ridge says about fighting terror, the terrorists only have to be right once...we have to be right all the time. The Borders Mgmt faces similar prospects...and I think their corporate resources would be wasted on trying to rein in idiots...and our energies would be better spent trying to convert the liberal idiots rather than trying to get them fired or punished or whatever and giving them another reason to cry "I'm a victim"... JMO...
Secret shoppers. We had them all the time when I worked briefly at a grocery store in SoCal. We had to assume every customer we talked to was a secret shopper, and had a checklist of dos and don'ts to keep in mind when we were dealing with them.