[wildmusings]

>The full argument is of the form "X is easy to do and hard to detect, so it would require police state tactics to have any hope of enforcing a law against it".

Plenty of crimes go unsolved in most cases. Littering, for example.

When you do catch an internet marketing company deanonymizing data, you can throw the book at them though. Strong penalties can serve as sufficient discouragement to others even if they are unlikely to get caught.