"Two Guys" joke

Two guys were swapping stories in the park one day
and one guy (a war vet) mentioned that during the
war he was captured and held for weeks without food.
The other guy asked, "How could you survive without
food?"
"It wasn't easy," he said. "But I had a big meal
before I was captured and learned to eat my own shit."
"WHAT? That's disgusting!" said the first guy. "I
don't believe you!"
Without a second thought the vet reached into his
pants, shit in his hand and promptly ate it on the
spot.
The second guy (now gagging) said, "My God! If you
can do that so easily, we can bet big money and rake
in a fortune!!"
"Sounds good to me," said the vet. "I can use the
money."
The next day the guy had set up a bet with two
wealthy but unbelieving high rollers.
"This I gotta see," said one of the gamblers.
"It ain't gonna happen," said the other. "No one
can eat their own shit."
"Let's do it," said the vet's buddy as he set down
a plate full of shit in front of the vet.
The vet looks down ready to dig in, when all of a
sudden he bolts from the table and projectile pukes
a streak across the room right on the two gamblers.
In a rage the gamblers kick the living crap out of
both the vet and his buddy, they take their winnings
and leave.
"We lost it all!!" said the buddy. "Why in the hell
didn't you eat the shit??"
"There was a hair in it!" said the vet.