Once you get your feet wet with the CLI, some things are way easier or faster to do in the Terminal. For example, searching. The GUI search is a pain in... wherever you want. In the Terminal I only write locate FILE and there you go. You get its path. If you wanted to find and edit your php.ini in the GUI, you'd have to type the name in the search bar in Finder, edit some stuff around there, edit the permissions (which also means editing them back when you're done), and then open it in your editor of choice. Inside the Terminal, it's as simple as locate php.ini, and then sudo vim /etc/private/php.ini.
Some things are easier to do the obscure way. For example, I like the Windows search better, because I can just type * in the Search... application select the "image" file type and boom, there's all the images in my computer. In OS X, I have to go through a lot of idiot GUI and dropdowns to get the same result.