For people who can afford and willing to continue even that huge amount of implemented taxes there's no stopping them to partake with this activities.
It makes sense. Just like how people treat the increase of sin tax in tobacco, liquor, etc. They don't bother with the tax as long as they want to take part in it.
In other words, people know how to adjust and there will be a time that they are now used to experience an increased tax.
Gambling operators also know how to adjust if ever they will be imposed by the additional tax of the government. They will pass it to their customers in a way that is not noticeable or proposed a win-win situation for both parties.
There is also yet another possibility, when the tax on something is too high like on liquor or cigarettes people will find products that did not paid those taxes and that are cheaper because of it, this is why governments need to be careful about how they tax something as too high taxes can generate black markets, and the same is true for services which is the category in wich gambling falls, if the taxes are too high then illegal casinos will appear and people will prefer them over the legal ones simply because they give better odds.
^ It is possible, but my question is if there is an illegal gambling casino which is you think they are much better than the regulated one, will you still gamble it there? For me, I don't, because most the illegal gambling casino has shady activity, not unless, the government will hunt them and force to stop operation which is very risky if you have a fund on that casino. That is why even how taxes will apply to the casino, they are still preferred this since they are running a business, besides, generating tax must have a calculation per annum and I don't think there is a casino that give more than 80% to the government, usually from 10% to 50% probably.