From the article:

Tayeb also notes that authorities are probing the possibility that the “mafia” could also be motivated financially by making “black films” — usually referred to in the West as snuff films — showing the brutal death, which are then disturbingly sold to twisted individuals over the internet.

Shawn Speagle talked about private Facebook rooms where these videos are sold using Facebooks payment system and the content moderators are told its not in violation of the rules.