If the land you are crossing is desolated yet captivating, then there is an excellent chance you are in what AAA calls the Indian Country. Misappropriation of the name aside the Indian country is where one comes to see incredible geological formations and to witness the progress of a 200 years experiment in civilizing natives.
You may think that the concept of bringing the benefits of Western civilization to autochthons is a thing of the past, offensive to modern sensibilities. But consider the restrictions on alcohol on Navajo reservation. The federal government forbids sale of alcohol on Indian lands unless the tribe allows and the Secretary of Interior certifies it. For the rest of us the default option permits alcohol unless local community curbs it. Which is more common than you think: a waitress in Blanding, UT apologetically remarked it's a dry town (and not because we were in the middle of the desert) when we tried to order beer with our dinner. The result, an utter lack of your favorite libation, is roughly the same but this is not a subtle distinction. Federal laws treat Indians like children. Just look at the extent of tribal jurisdiction over Indian country: the tribal court can only rule in case when both the victim and the perpetrator are Indians and only when the crime is a misdemeanor. Felonies and crimes affecting non-Indians are deemed to difficult to be left to native judges.
Current state of affairs is obviously better than forced relocation or confiscation of livestock to prevent overgrazing. It's better than deciding whether tribal lands should be privatized or not - actions that federal government took in the past under the premise of protecting the indigenous population. And did I mention that the lands allotted by the federal government to Indians are the least productive and most forsaken in the Union? There is no need to put up signs that you are leaving the reservation because terrain suddenly and markedly improves.
Given all the efforts to civilize them, it is actually quite amazing how persevering Navajo, or Diné as they call themselves, are in resisting the Western culture, and how enterprising they are in exploiting it. Navajo didn't enter the area of the present day US until 1400 CE doing a bit of colonization of their own and engaging in raids against Anasazi - the ancestors of modern Pueblo Indians. Yet they managed to secure the largest reservation of all. They also nominated themselves as guardians of sacred Anasazi ruins and artefacts.
The appropriation of their lands by white settlers left Navajo people in dire need of income. Once the federal government decimated their sheep, curtailing prosperous wool rug industry, Indians had to resort to fleecing tourists. They are not greedy people. $5 per person to drive across Monument Valley is not expensive. $2 for an opportunity to pose for a horseback photo against picturesque background is positively a bargain. A tip given a guide for showing dinosaur tracks and supposedly fossilized dung won't harm a wallet, only the conscience of its owner. Jewelry sold everywhere on the reservation - including overlooks of Canyon de Chelly National Monument - is cheap. Even more so when its only link to Navajo heritage is the ethnicity of a person selling it. History turns full circle with Indians selling beads to Anglos. Too bad that this trade is not as profitable now, as it was when we acquired New Amsterdam.