That’s not haram... Even when you work and get paid, the money is still coming from all kind of haram sources but as long as you earned it halal it’s considered halal income in islam..what the money did before it got to you doesn’t matter, that’s some extremist view point. Also, taking welfare is halal if you need the help and don’t lie or commit fraud (like a lot of people do)....If you brought up the fraud angle, it would make sense because that is a common haram thing people do but all that talk about tax collected from gambling or whatever doesn’t make sense..