I found the following story posted in the March 3, 1944
issue of the Carteret Press
(scanned and hosted by the Woodbridge, NJ Public Library):
MOTOR TRIP HOAX
Los Angeles — A new kind of hoax was pulled when four men answered an ad asking for passengers on a trip to Raleigh, N.C. The driver picked them up, collected $50 from each and then stopped at the post office. He went inside and that was the last the passengers saw of him. The car had been rented.
But I'm having trouble understanding exactly how the scam would have been profitable. First, if the car was a rental, wouldn't it have been easy to find out the identity of the scammer? Unless, of course, he used a fake ID to rent the car. Second, some kind of deposit must have been required by the rental agency. By abandoning the car, the scammer would have lost this deposit. But if he took in more from the victims than he lost on the deposit, I suppose this wouldn't matter.
Perhaps I just answered my own questions!