Commercial gambling ads will be available only in the countries who supported gambling to grow and probably your government let this happen because they admitted gambling as industry and can be good source tax for them but besides all of it i think they will also thinking the risk behind it especially i read your post that there was casinos near to high school locations and it's very risky to childrens at there will attempts to gambling because casinos is too easy to be access
All gambling sites going to pay their taxes to the government? I don't think the gambling owners how much good to pay this so better to avoid support gambling in their countries if they want the future of the country to be well. Gambling earnings or not good father future just enjoy gambling.
Actually it's true that in gambling business it's a good source of taxes for the government because it's a big industry and they can make a lot of money to it. However, there are countries that are not gambling friendly, they only give license to a small number of gambling establishments so they cannot maximize their taxes on gambling, maybe they have other bigger source because a government lifeblood is tax, so why would they refuse others.
Also, with the advent of crypto, there are already a lot of online gambling sites that has no license because they do not need to as the people still trust them, it's only reputation that is important in gambling so even if it's not operating with a license, there's still a potential to grow and succeed.