you could get the feature from any number of areas, I'm just saying that in a lot of cases, the GUI can act as a "gateway" to understanding the functionality of

you could get the feature from any number of areas, I'm just saying that in a lot of cases, the GUI can act as a "gateway" to understanding the functionality of the application and the CLI can then be used to implement/extend/whatever said functionality for personal use. Handbrake is one that I think implements this well.