Chief Chaos, I didn't see your post until just now. Maybe it isn't necessary for oil companies to remove people so they can access the oil, but that fact doesn't seem to stop them from doing it. It's happening right now in parts of South America, and here is a case of it happening right here in the US (in this case, it is oil as well as other interests who are responsible)

THE 10 MOST FREQUENTLY ASKED QUESTIONS ABOUT THE NAVAJO - HOPI LAND DISPUTE WITH A REBUTTAL BY AL SWILLING FOUNDER OF SENAA

You need to read the rebuttal to get to the part I'm talking about. And in this case, the US government has been using exactly the same kind of divide and conquer tactics that the government of Sudan has been using... creating conflict between peoples that either didn't exist before, or that the different parties were able to resolve on their own prior to government interference.