Civil forfeiture and DEA is a separate problem unto itself, and you’ve always hit on the key points: DEA operates within the country, whereas customs is at port of entries. DEA’s corruption and geographic reach mean they have caused far more problems than any customs agent, in pursuit of a 1990s zeal that “drugs are bad” and expanding that into a parallel law enforcement system, despite already having a federal law enforcement department: the FBI. Civil forfeiture should be abolished as unconstitutional, violating due process, equal protection, and property law.

So yes, once you’re in the country, there is a risk to carry around large sums of cash. But that’s hardly connected to the customs declaration requirement, and certainly cannot be connected to the declaration requirement on the way out.