Z I agree that the protests are now on federal land.  I thought they were still on private property but those protesters have largely been removed/arrested already and the camps moved to federal property.  Even then though, I'd be interested to see your opinion on the Bundy Ranchers versus DAPL protesters and why it's okay to use federal land in one case but not the other.   

As far as being compensated for lands, that would apply to all private landowners, not just the DAPL.  In order to "give" the Sioux that land back, they would have to take it from private landowners, farmers, ranchers, etc.  It would be difficult to just upend everyone currently living there based upon a treaty signed in the middle of the 19th century.  There are currently 8 pipelines running through North Dakota.