Maybe there should be a process where they can DISENROLL bad diamonds, or any member for that matter. There is a point where you do not want their business. I run a business that involves dealing with the customer weekly and we at times do ask them to leave and to find a place where they are happier. Sure, this cost's us money, but there is a point where it probably costs more in upset employees, offending other customers, etc.

If that ... acted like the OP indicated, I would love to take his name and bar him from the chain unless he personally appologized for his actions.

The customer may always be right, but this guy is no longer a customer, just a jerk.