I don't pretend to be an expert on the history of reservation/state relations. I'm no advocate of the indians, but apparently there has been an erosion of indian soverignity when it is convienent for the state.
To sum it up, I think the root of the problem is obscenely high taxes and consumer behavior that results in taxation avoidance. To beat up on the indians soils the hands of everyone involved in the process. There are many people who have prefected the art of taxation avoidance by leaving the state, as the US census figures will tell you.
The indians are a symptom, not the disease...