Emacs does this to create its image with all the added functionality above the minimum required to run elisp, then has a mechanism to pull in text files because

Emacs does this to create its image with all the added functionality above the minimum required to run elisp, then has a mechanism to pull in text files because elisp is just text anyway. They just chucked the old system for a portable version of it, but until this last release, they still had to option of doing it the old school way.