I did find somewhere online that one of the producers of the the show said that it is mainly setup by the person being exposed on Catfish, and the rest of what you see is just for presentation. They allegedly leave Nev and Max in the dark about everything, so their reactions are mostly "real".
Nev: The Hairy One
in Catfish [V]
Found this Catfish Parody pretty funny. You might want to check it out: http://www.youtube.com/watch?v=oIimPjOEcKo
I did find somewhere online that one of the producers of the the show said that it is mainly setup by the person being exposed on Catfish, and the rest of what you see is just for presentation. They allegedly leave Nev and Max in the dark about everything, so their reactions are mostly "real".