Why don't we know this?

A few weeks ago, we discussed Native Americans. Mr. O'Connor mentioned that he could only name a couple dozen or so tribes. I myself was stuck after the first 15 or so. It seems like a sporcle quiz: how many can you get?

I checked on Sporcle if there was, in fact, such a quiz. I could only find quizzes such as "can you name the most populous Native American tribes?" To be honest, I'm almost relieved that there wasn't a quiz asking for all 564 nations to be named. I'm certain that no one would be able to do even passably well, unless they were a scholar of Native American history.

I remember being in Arizona (where my family goes at least once or twice a year, to Scottsdale) and reading a book by Tony Hillerman about how there was a Navajo word for white people, but no word for a Native American who was not a member of their tribe (in other words, no name for the race of Native Americans). I thought it was strange, at the time, but I guess it makes more sense.

In the book the Shadow Catcher, a part fiction/part biography of Edward Curtis (a photographer known for his dishonest portraits of Native Americans), the author mentions how strange it is that so many car companies and models are named after Native American tribes. Think about it--Pontiac, Tahoe, Navajo, Comanche, Cheyenne, etc.

Is it ethical to portray Native Americans as something wild, something you need a Jeep to traverse? And why don't we know more about these people?