"RESTAURANT ETIQUETTE" joke

A man is crawling through the Sahara desert when he is approached by another man riding on a camel. As the rider approaches, the crawling man whispers through his parched lips, "Water. .. please. .. can you give. .. water. .."
"I'm sorry," replies the man on the camel, "I don't have any water with me. But I'd be delighted to sell you a necktie."
"Necktie?" whispers the man. "I need water!"
"They're only four dollars apiece."
"I need water."
"Okay, okay, two for seven dollars."
"Please! I need water!" the man exclaims.
"I don't have any water, all I have are ties," replies the salesman, as he heads off into the distance.
By now the man has lost all track of time, crawling through the desert seemingly for days. Finally, nearly dead, with clothes tattered and skin peeling under the relentless sun, he comes upon a restaurant. Summoning his last bit of strength, he staggers to the door and confronts the head waiter.
"Water. .. can I get. .. water," the dying man pleads.
"I'm sorry, sir. Neckties required," replies the waiter.