These services does not require manipulating real money.
To run the service, it requires a device connected to the internet, that all.
You can find a lot of way to host it in a country that don't have these requirements, or to host it anonymously.
Mixers are now a target for law enforcement though, just so you know.
I know, but you can easily do a service on a decentralized service really hard to shutdown, anonymously.