Why would people pay for the taxes? it's the gambling operators that will pay taxes to the government, people are already losing money to these gambling operators, so that's even bigger than paying taxes, I don't get your point.
I agree, they should not impose the taxes to their users, they are making a lot of money, from their clients, they are the one should take the burden of the taxes, gambling sites are not selling products so they cannot add the taxes to their products.
The taxes that the government is imposing is for them to have a support coming from the government.
That's why I was confuse because some were thinking that it's the users who are paying the taxes when in reality, users are the one spending money to make the casinos profitable. Maybe there are countries who are really strict with imposing taxes, like if you won money in casinos, your winning is taxable, but that one is quite complicated to me.