Somehow there are certain concepts that people repeatedly buy into automatically, whereas even a moment of logical thought would send them running. Not surprisingly con men know of and use these psychological quirks a lot. The "seed money" concept is and has been a very popular one. A very common racket, at least in the recent past, was the con man coming up to the "mark" and claiming to have discovered some money in the street. For some reason the con man offered to share it with the mark, but only if the mark provided some of their own money as "good faith" while the con man went to the bank to split the found money. Of course the con man ends up with all the money. But why, if one thinks of it, is there any need for "good faith" money at all? Similarly, con men would sell people machines that "print real currency" because the con man "needed some quick cash." ???
There must be some subroutine still in our brains that somehow worked in neolithic society (hunting wooly mammoths?) but in current day society convinces us in a bizarre way that these things make some sort of logical sense and that we should thereby give away our cash.