Perhaps the people who make the laws leave these tunnels they may need to crawl though some day.

I don't think so.

Criminal laws tend to get drafted and applied narrowly - more narrowly than civil laws, and even moreso than administrative practices. The idea is that criminal penalties are the most severe sanctions. You want to reserve them for deliberate, intentional malfeasance. You generally send people to jail for doing something intentionally wrong - or something so reckless and negligent that it's tantamount to intent. The goal is to try to draft criminal laws so that it is relatively simple to avoid breaking them.

When it comes to classified information, people who work at highish levels in certain government agencies (like Defense or State) are going to be dealing with classified materials all day long. Constantly, in almost every aspect of their job. But classification of information is complicated and imperfect - material that is classified isn't always identified as being classified, it isn't always classified at the time it is generated, and different agencies can (and do) disagree about what is classified. It is inevitable that someone who deals with a ton of classified information will make mistakes with that classified information at some point.

That's why the criminal regulations on classified materials are drafted the way they are. It's a crime to remove a classified document from a secure place and move it to an unauthorized, insecure place - because it's hard to do that without (like Sandy Berger) taking some actions that the person should know in the moment are violating that law. Receiving classified information that wasn't marked as classified (for almost all instances), which you didn't remove from anywhere, which was sent to you by someone else, and that you have clearance to receive? Less than obvious. So it's not surprising the statute isn't written in a way that would make that criminal.