i live on a small reserve and i work at a VLT vendor. i know that at our place we make a stupid amount of money a night and the deposit we make at the end of the night goes to our cheif and council. we don't get taxed on our profits.
not saying that's the deal with other reserves, but for is it's an easy way to make money for our band and reserve. although honestly, most people don't see any of it because our council is corrupt.
but that's a story for another day.