This is not a technology or privacy problem - it's a legislative one. If it's illegal to do X, then it seems reasonable for the gov't to enforce that - the more efficiently the better. And if enforcing it seems wrong, then maybe it shouldn't be a law.

For another toy example, what if speed laws in the US were fully enforced 100% of the time - they would be yanked immediately, because they are dumb and mostly just used to fund the police. We only tolerate them because they aren't enforced on us very often as individuals. It's like a medium-skill lottery to see who pays for the police.