It is actually not such a silly example. Several years ago, government agents broke into a CBS news woman's house, installed a fiber channel cable, physically broke into her Mac computer and installed extra hardware key loggers to watch what she was writing, and, it was discovered when her computer was examined by forensic IT specialists, also installed some hidden photos deep inside a couple of libraries on her hard drive.
In those photographs were some CLASSIFIED and SECRET government documents hidden via steganography techniques inside the images. They had been placed there for future use when and if they government ever wanted to arrest her and wanted a pretext to charge her with spying.
These kind of photos can be sent via email, messaging, or even Facebook.
Thanks for the example. And for other readers, don’t forget that a federal judge just sanctioned about half of the DOJ lawyers by denying them the right to enter a federal courtroom in 26 states for lying to him. All large organizations tend toward corruption.