Surely to fuck you could write a program that would do it without all the fucking phones and/or the human?
Someone should tell them there's been a digital revolution.
A manual approach would likely be the most profitable option in this situation, for obvious reasons when you think about it…
The short-term labour costs in this region would be dwarfed by the financially prohibitive outlay of a technologically more efficient system (regardless of magnitude), given the resources we can infer are available from this picture.
Undoubtedly there are far larger operations, using all the bells and whistles of modern software and hardware to the same ends, but don’t hold your breath to see photos of them.