In Malaysia, any lottery or casino winnings will not be taxed. If you win one Million Ringgit Malaysia, you can just keep that money, not having to pay any tax for it. But, in US country, once you win on any lottery or casino game. Then, you will be taxed a 30% withholding tax.
However, as a non-resident you can claim back the withholding tax. This will depend on which country are you from, you can file to have some or all of the gambling tax refunds to you. Obviously, this service will bring more benefits to those international gamblers across the world.