Mystery shopping allows for a company to understand how their training and support is benefiting their staff members. The life blood of any company is their customers. The fact that a company would hire mystery shoppers to determine if the system they set up is working, for the customers and the staff, is a noble effort.
There are just as many companies who do not care about customer service or whether their staff has the proper training to keep the company in good standing with who matters.
Not to mention, I am sure the company has the employee sign legal paperwork that shares that they may be subject to review or a mystery shop.
What you have to remember here is why the company is contracting to have mystery shops completed.
Many companies understand that their customers are the life blood of their business. They know that in order to stay in business, they must make sure their customers are being taken care of, as they designed and their product is being represented properly.
We all work very hard for our money and I admire companies who understand this and only want the best for us, as consumers. The mystery shopping companies, the legit ones, will make sure that the mystery shopping is handled in an ethical way. After all, they are the experts in the field.
As mystery shoppers, it is our job to treat the agents or staff that we are shopping as if we were in their shoes. Allow them to do their best job possible based on how they were trained with minimal interruptions. Of course, you are open to your opinion about this, yet mystery shopping has been around for a long time and I am sure it will continue to be a valuable component of the customer service model.