IP logging is an inbuilt and non-configurable feature of ShoutCast DNAS and IceCast so no, there's nothing we can do about that from within Centova Cast.
Granted I'm neither a lawyer nor a resident of Germany, but bear in mind that virtually every web server on the planet maintains very similar logs which also contain IP addresses. So unless it's illegal to run a stock Apache/nginx/lighty server in Germany I'd be surprised if you ran into any problems doing something identical with a ShoutCast server.