Political.

Given that the land (and lives) of many indigenous peoples was taken for grazing.  

The history of American Indians is well known. *The bison were exterminated, in part, to create and maintain a dominant “cattle culture” across the Great Plains and the West—and, unfortunately for Native Peoples and wildlife—it worked.* http://www.buffalofieldcampaign.org/about-buffalo/buffalo-and-native-americans

Australian indigenous people suffered a similar fate. *n the face of continuing resistance, and justifying their actions by a belief in the superiority of their civilisation, the colonisers pushed Aboriginal people off the fertile lands into controlled settlements.* http://www.clc.org.au/articles/info/the-history-of-the-land-rights-act/