The structure of the forum (not just related to 1xbit but all websites that range between highly suspect and out-and-out scams) is as such that they are not moderated in the forum and that is why they have been space to breathe here.
As you rightly said, we cannot kick them out and as they have lost all concerns about their trust ratings there is not way to tackle them. One way to cause some form of disruption to their plans within the forum is to discourage members from participating in their signature campaigns.
There is no solution to the problem unless they authorities close it down or they actually address every single complaint against them and settle all outstanding issues then start a journey towards being a genuine trustworthy business. Unfortunately, things do not seem like they will change any time soon.
I dont think 1xbit is a worthy discussion. We know they know we cant kick them out of the forum. Its obvious they do not care about their trust rating on bitcointalk, they get enough publicity outside the forum with zero or minimal confrontation. No one except us here at bitcointalk care about the illegal activities of 1xbit, they have zero confrontation on the other websites they advertise their casino. if you search on the internet is 1xbit a scam you will find a bitcointalk thread about 1xbit on the first page. Thats why the victims of 1xbit keep on coming here to lay their complaints forgetting that bitcointalk isnt the official page of 1xbit.