"Giving The Thumbs Up" joke

A successful businessman flew to Las Vegas for a weekend of gambling. Unfortunately, he lost the shirt off his back and had nothing left but a quarter and the second half of his roundtrip ticket. If he could just get to the airport, he could get himself home. So, he went out to the front of the casino where there was a cab waiting.
He got in and explained his situation to the driver. He promised to send the cabbie money from home, offered him his credit card numbers, his driver's license number, his address, etc. but to no avail. "If you don't have fifteen bucks, get the hell out of my cab," the cabbie yelled.
So, the businessman was forced to hitchhike to the airport and arrived with barely enough time to catch his flight.
A year later, after having worked long and hard to regain his financial success, the businessman returned to Vegas and won big this time. Feeling pretty good about himself, he went out to the front of the casino to get a cab ride back to the airport.
Lo and behold, who should he see out there, at the end of a long line of cabs, but his old buddy who had refused to give him a ride when he was down on his luck. The businessman thought for a moment about how he could make the guy pay for his lack of charity, and he hit on a plan.
He got in the first cab in the line. "How much for a ride to the airport?" he asked.
"Fifteen bucks," came the reply.
"And how much for you to give me a blowjob on the way?" he asked.
"What? Get the hell out of my cab!" came the response.
The businessman got into the back of each cab in the long line and asked the same questions, with the same result. When he got back to his old friend at the back of the line, he got in and asked, "How much for a ride to the airport?"
"Fifteen bucks," the cabbie replied.
The businessman agreed and off they went.
Then, as they slowly drove past the long line of cabs, the businessman gave a huge smile and thumbs up sign to each driver.