Generally speaking, a UI DOES have a use case - when you can't be bothered to learn the configuration language and its keys / values / nuances. The UI can help you create a sane and safe config, instead of having to scour the internet for - potentially outdated - information.
Mind you, I've had more trouble with that with Apache given how they changed their config files around on multiple occasions.
Mind you, I've had more trouble with that with Apache given how they changed their config files around on multiple occasions.