Catfish the show finds the people's who are borrowing other photos to find online love. I guess the payoff is that they can win over good looking people, text that they love them and hear it back without meeting. Usually the person who is being catfished is for real and WANTS to meet the perceived object of their love.
The catfish show guys find the real people behind the stolen pictures with tech tricks, confront them gently and everyone eventually meets and the person who faked being somebody else and stole another's picture usually cries and says she was lonely.
From what I have noticed, those who steal pictures and make fake names to go with somebody's gorgeous picture actually tends to be less attractive than average and perhaps has trouble finding love in real life. One person said she didn't like herself so she became someone else.
I guess those things are the sad payoffs for them. But it's scary that they can steal a strangers FB photo and do what they want with it. At least in my opinion it's scary.