But then it happens again 2 or 3 months later anyways ...
Oh, right, decrypt it real quick in the app, right? How will you protect that decryption key?
From the way it looks, the security precautions they are failing at are so trivial that most developers probably have more secure personal servers / computers.
A lot of these attacks are trojan already breached the network and insider attacker. The latter is often due to infection (e.g. USB, browsing problematic website). Encrypting file, encrypting SSN field is not a full solution but is definitely a really good solution.
Sure you can physically intercept mail - but there is a huge difference in magnitude. I wager you could not in any practical way intercept millions (or even thousands) of paper records without being traced.
That's why these poorly protected digital records are such a gold mine.