Re: legality
Let's just say it's not illegal .. until they say it is.
I've been caught on Indian land (not these two) and been simple asked to quit playing. I know this is gonna open up a long tirade by those who feel their rights are infringed on everytime they set foot on the reservation, and that's fine, but the fact is the laws are not the same there, they can probably be changed on a whim, and you better know that before you go.
Of course, most of their business is dervived from non-Native Americans and they can't stand a lot of horrible bad publicity just like any other retail establishment -so they try to treat you as you would expect them to do.
But, I'm always on my best behaviour at an Indian place. 99.9% of time it's just what you'll expect. But that 0.01% time it's not, I imagine, will be a real bummer.
Last, and I'm not exaggerating here, when I cross the 'border' I don't speed, I don't float stop signs, and I don't squeeze the yellow lights. I make sure my car tag is up to date and my insurance card is handy. :) You think I'm kidding; I'm not. I am one good citizen on the reservation. If you are worried about explaining to the Fed's at the airport about all that cash, wait till you get to explain to the Tribal Council what you were doing with all that cash when the traffic police stopped you for going 5 over. No thanks!
So be extra nice when they catch you; and smile a lot.