Beings called "life stealers"

Iv discovered a race of beings on a planet. I call these beings "life stealers." They seem to try to profit off of everything around them drawing the energy to themselves and returning little.

Their environment, each other, it isnt hard to recognize that if they continue taking more than they give thier planet will no longer be able to sustain them. Unfortunately they dont seem to know that. If you can me warn them it might save our lives.