Can't say i'd be apologising to someone who was that rude and abusive.
I got this one from a customer the other day. The Entitled Generation. Didn't like being told that i had to pack, weigh and measure the cartons for large orders in order to give postage quotes and i don't do that without payment. Told me it was illegal to not give him a free postage quote and that he was going to ring consumer affairs. This was his response when i told him to go ahead.
Looks like i saved myself an hours work as he say's he was never going to buy it in the first place.