It would be interesting to know how accurate the video is in terms of what percent of the substances are actually obtained through child labor or slave labor.
To obtain extreme material wealth through industry, one person or group must exploit others by paying labor less than the value of what labor produces, or by charging more for a product than what it's worth relative to other products.Our entire political-economic system being predatory, is somewhat due to the belief that's it's morally acceptable to exploit others to acquire wealth.
Combine predatory behavior with competition to exploit what is exploitable -- and we have the extremists among us destroying the planet, other people, and entire cultures while they do it.