I see them in many public bathrooms. Libraries, for example. I've also seen them in the bathrooms of some big box stores. All airports, all publicly owned buildings. Many gas stations.
I don't live near a reservation but I've gone on short-term mission trips to Wind River and Pine Ridge. Diabetes is a huge problem both because of their genetic predisposition, abundance of free/low cost high-carb food, and alcoholism. And yes, all thanks to the federal gov't.
But have you seen the movie "Wind River" ? It's not a happy movie, by any stretch, but I thought it was well done.