I don’t even have remarkable winnings from gambling so I can tell that I’m not paying taxes with my gambling habits. And if ever I won huge amount, most likely from lottery, the organization itself already deduct an amount intended to pay for the tax. So I don’t pay it personally since the prize amount has already been reduced probably by 20% out of my whole winning amount.
Yes, if it's legal, I think you will definitely deduct tax on your winnings, but if it's illegal, maybe you don't have to pay tax because it's clearly illegal, so it will be a problem if you pay tax and say you're a gambler, actually this depends on the country, whether it's a lottery or other gambling is legal or illegal, if it is legal I believe that your lottery winnings will definitely be taxed by the organizer or organization you are referring to.
I probably won't pay taxes on my gambling winnings because in my country gambling and lotteries are illegal so it would be nice to keep all my gambling profits for investment or use my gambling winnings for fun, so no need to pay taxes for countries that consider gambling and the lottery is illegal, besides I'm just like you never get a big win so why think about paying taxes