In the US, when dealing with customer service reps, it is of utmost importance to be authoritative: show them who’s the boss and ask to speak to a manager every time something doesn’t go your way. Customer is King, even when customer is an asshole, even when he’s wrong. Especially if he’s wrong.
At least, that’s what any wise American will teach you, with a conspiratorial look that’d make you think he is letting you on the secret masonic handshake of the customer support guild. Equipped with these conceptions, he will then proceed to use them abroad, wherever he goes, perpetuating the accepted worldwide standard for Ugly Americanness…