They are tagged as "incompatible". No need to panic. It's a sandbox game, there will always be some poor taste in workshop submissions. It's been very minimal, it's rare.
There is nothing stopping anyone from putting this content in their parks. It may be hidden, only found by someone exploring the depths of park. Workshop contributors should warn about it I suppose, but that's impossible to enforce.
All you can do is unsubscribe from stuff you find offensive, and take note of users on Steam with good reputation, good comments, which is 99.9% of contributors! It's not all about obscene language and rude body parts. There's endless social, political and religious references that could potentially be used in offensive ways. The *potential* for this only reflects on the awesome power of the modern sandbox game!