How about on roulette wheels?

There are this thought as we have seen it work before for a group of people to find a bias roulette wheel and won big money until they got busted. But that was before, I think casinos have adjusted already with this myth and so they interchange roulette wheels so that you can't find any flaws on them and take advantage.

Or probably have measured everything perfectly that the wheels are really balance and you can't find any biases.