Mondo Miami emerges from a long line of film history.
Incredibly, the first documentary ever made, begins with a title card explaining how the movie is, woopsidaisies, a reconstruction.
A reconstruction of reality and not a document of reality as it actually occurred.
If you think about it, you'll see that the movie is, on some base level, a true documentary.
This man, Nanook, no longer exists.
His exact situation no longer exists.
Robert Flaherty no longer exists.
The technology and means of distribution that created the movie no longer exists.
In this sense, everything captured by the movie, although a blatant re-staging and re-creation of unadulterated life, is documentary in nature.
A few years later we have the first grand expression of the mondo genre, with Ingagi (1930).
Ingagi comes from the same tradition that created Nanook: the fad of the ethnographic and travelogue documentary genre.
However, unlike Nanook (which tried to present itself as a serious picture with sociological significance), Ingagi is a straight-up exploitation film.
With exploitation, the function is shock & titillation - not education.
So, we have the emergence of the shockumentary.
This is complete with advertising campaigns declaring Ingagi as "The Wonder Film," promising "A Million Thrills in the Heart of the African Jungle" - highlighting the various extreme aspects of the movie that would draw a crowd into the theater, that would make the random (male) bystander empty out his wallet for an hour's experience.
Because the market was the dominant consideration on the overall aesthetic of the movie, certain corners were cut in exchange for exploitation value.
One cut corner was integrity.
Why waste so much time and safety integrating into a new group just to get some footage?
Why spend time waiting around for something amazing AND real to happen?
Because money talked, and time is money, the ability to crank out material fast was favored over realism.
So that idea was thrown out the window.
Ingagi, then, features a lot of fake footage.
Even to the point of creating fake animals and fake cultural practices.
Remember: the point was to shock and titillate, not educate.
Hence, for example, the "creation" of the Tortadillo:
This is a creature fabricated for the film in an effort to shock the audience with extreme exotic life (aka, giving them their money's worth).
Oh, and there's plenty of nudity.
And a man in a gorilla costume chasing bare-breasted women, presumably for sex.
The Tortadillo, by the way, was a turtle with wings, scales, and a long tail glued to it.
Also, the natives in the film, and most of the scenery, were not from Africa... but Los Angeles.
So, you see, this active deception in the exotic exploitation film, and then later in the mondo movie, all under the umbrella of the "shockumentary," is a function of the market demands of these movies.
We need product quick, and we need it cheap.
A true documentary film in the purest sense, however, requires authenticity and immersion.
So the obvious way around these "constraints" is to simply fake the footage.
But not everything is faked. Only the most shocking and titillating aspects.