Back to work

It was fortunate that Keith and I were better today and able to go to work, otherwise we might have missed today's 'customer from hell'. He came in with a printer and said the red light was lit and it wouldn't work.
"That means the ink cartridges are empty," said I helpfully.
"Oh no, it can't be that, it hasn't shown up on the ink monitor display on the computer."
Then he said he would like it done as quickly as possible as he needed it for work. So, ever obliging, Keith began work on it and discovered - guess what? - the ink cartridges were empty. Of course, to prove the point, he had to put new cartridges in. I rang his wife and told him it was ready and an hour later he arrived to pick it up. Well, we didn't expect a medal, but it would have been nice if he hadn't ranted about the fact that we had put new inks in when he already had plenty at home. He refused point blank to pay for the inks, we managed to get the money for the work done out of him and he swept out of the shop, throwing paper from the printer all around him as he went and yelling insults at us.
Why do we attract all the anti-social morons???