I don't know for certain, but it may not even involve cooperation from sellers.It appears many sellers are willingly giving up their customer lists.............
How hard could it be for a government agency to see in detail a transaction between an individual and a company that sells on the internet?
Especially if said company has gotten the attention of the Feds by openly selling an illegal or regulated item by calling it something that it is not.
The easiest fix for all of this would be just to eliminate the stupid laws that make it difficult for the average person to own a hearing safety device.