Pretty sure Apple at the very least injects a hidden file that easy to see if you plug the drive into an Apple device then into a non-Apple device; no idea why they are adding it, though 99% sure it is for file operation administration.
Edit: Appears at least one of the files added is called “ “.DS_Store” and is still around:
I learned a roommate was snooping around my flash drives because of this. A bunch of .DS_Store folders appeared in a drive that I had never connected to an OSX machine
It's the equivalent of desktop.ini on windows, so yeah finder customisation etc..
Expect Mac software does fuck all to prevent it "leaking", so pretty much every zip from a Mac user contains one of these in each folder. Only case we had desktop.ini do the same was with Dropbox.
DS_Store just includes basic window configuration information for Macs. Stuff like list vs icons, size of the columns, etc, so you have a consistent UI look when you're accessing your remote drives.
It can be toggled to avoid it on removable devices when they're connected to Macs. It's benign, though I guess annoying to some non-Mac users.
Edit: Appears at least one of the files added is called “ “.DS_Store” and is still around:
https://appleinsider.com/articles/22/02/19/google-drive-user...