Roulette is just the old version of dice, it doesn't really need to be that important, considering the zero on the table (which we can see from the picture) the red or black will never be 50% chance, you can keep on playing at red forever for example and because of the zero on the table the result will never be 50% red for you, it will always have a house edge of zero coming in time to time rarely.

Even though the deposit of new coins are much more important, it brings out the fast and cheap deposit and withdrawal. That is the difference between casinos and exchanges, exchanges have millions of coins yet they charge you a lot to withdraw whereas casinos only take out the required amount most of the time and having something like nano or doge would allow us to both deposit and withdraw quickly and cheaply.