You could certainly use a ZIP file as a read-only directory with limited functionality. It isn't possible to update an existing ZIP file, and if you had an executable program in the ZIP file, you would have to copy it out to a real directory before you could run it. Likewise you couldn't treat anything else in it as a file.
But apart from that, a ZIP file is a good way to keep a bunch of files together in one place.
subject: Is it possible to read and run files directly from a zip file?