I use emacs because it's available everywhere, and can do everything I want. When I decided that I needed to learn something ubiquitous, i started with gvim. But it wasn't for me, so I went with emacs instead. It doesn't matter what you use, as long as you can do what you want. I think a conscious choice of editor is a fairly good indicator of a good programmer, regardless of the actual choice.
That is kind of the thing about Emacs and Vim, right? Vim is a text editor. Emacs is... well, Emacs is a text editor, too. And then an outliner, a news reader, a file manager, a source control interface, a psychiatrist, tetris, a mail client, an IM client and pretty much anything that can be represented in text and simple images.
I used to use Vim for a year or two. Then Emacs, and I haven't looked back. Actually, that is not true. I have looked back quite a bit, since Vim is hands down a better text editor than Emacs. But I can't go back to IDEs really and Vim just sucks as a development environment if you can't combine it with a Unix command line. Emacs is the only great platform agnostic development environment I know, even though it might not be the best text editor out there.
And yeah, there is Evil-mode. It is quite lovely, actually. But my brain just can't cope with dealing with Emacs and Vim simultaneously.
So, I totally agree, you'd be insane not to use Emacs, really.
But you'd be insane not to use emacs.