Le client est roi, mais... le roi est mort.

This excerpt is from the eight lessons about the French by Elain Sciolino, the former New York Times correspondent in Paris.

Execution of Louis XVI.

Anyone who has lived in France can testify that after sales service and, generally, customer relations is a horror area of French life. Often worse than people-state relationship in the country.

3: The Customer Is Always Wrong
 
It is hard for French merchants to admit they are wrong, and seemingly impossible for them to apologize. Instead, the trick is to somehow get the offended party to feel the mistake was his or her own. I’m convinced the practice was learned in the strict French educational system, in which teachers are allowed to tell pupils they are “zeros” in front of the entire class.
A doctor I know told me he once bought a coat at a small men’s boutique only to discover that it had a rip in the fabric. When he tried to return it, the shopkeeper gave him the address of a tailor who could repair it — for a large fee. They argued, and the doctor reminded the shopkeeper of the French saying, “The customer is king.”
“Sir,” the shopkeeper replied, “We no longer have a king in France.”