I meant the case when you have to use an other machine and naturally emacs users want to use emacs even there, so that's given. But on Windows, for example, python may not be installed, so that's an extra install, while if you have your usual scripts in emacs then it's just a matter of installing one's emacs config which one does anyway.

I use python too when it's the less hassle. E.g. when parsing a page with BeatifulSoup which would be more cumbersome in emacs without BeautifulSoup.