I guess you don't like being able to upload images/files to a web application.
This (or another in a litany of ) WP vulnerability usually involves uploading a php script which exposes a bunch of extra server-side functionality (download any file, list users, access MySQL dbs...) through WP's file upload manager, which WP seems slow to fix on occasion.
That said, there's no reason a developer couldn't do the useful part of your suggestion —run a checksum of their application files when the upload to the server, then use that to identify anything that's been monkeyed with. I might start doing that, actually.
But there's no way I'm spending a dime with YourHostingCompany(TM), which requires I make simple code changes via VPN. Will you give me SSH access, even?
"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." -- Bertrand Russell