But animals and nature in general don't claim more than they need. When a system in the body developed and starts taking more than it needs we call it cancer. From what you say, even you realise the ills of capitalism regardless of the presumed benefits. My point is we need to create a system that serves us all instead of standing idly by while so many continue to suffer.
We're all born to the earth. Capitalists claim the earth as property and force the rest of us to pay for it. The system needs me fed to stay alive. It can't exploit a dead man.
I'm neither American, nor your teacher but here; http://www.collective-evolution.com/2014/09/13/7-ways-marijuana-legalization-has-already-benefited-colorado-in-only-8-months/
Drug prohibition is more problematic than decriminalisation.
At the bare minimum every person deserves to have good food, a comfortable place to sleep, and quality health care. For the millions in the lower class and even the middle class, buying junk food to survive is an inescapable reality of their lives, ultimately leading to sickness and disease and perpetuating the cycle. So yeah, I am biased against a system that makes people suffer.