Storing value. Smart ass answer, I know. But it's true.
As a private currency, Bitcoin is like a screen door. So I don't know why you'd use it for illegal activities.
Just look at the stories of darkweb markets they take down. Thousands of sellers, catering to tens or hundreds of thousands of buyers.
There is no other market anywhere in the world using cryptocurrency to that extent.
Storing value. Smart ass answer, I know. But it's true.
As a private currency, Bitcoin is like a screen door. So I don't know why you'd use it for illegal activities.