They don't know that bitcoin will be the new "cash"

I bet that when Sweden becomes totally "cashless" Bitcoin will become very popular there.
It is an illusion that you can get rid of the black market by making paper money obsolete.
You definitely got THAT right!
There was word some time ago that some drug dealers in some parts of the USA had started taking Tide as payment for drugs. (Yes, Tide the LAUNDRY DETERGENT!). And some drug addicts have been stealing it in somewhat large and even small quantities in order to pay said drug dealers. It's gotten so bad until many of the pharmacies that sell it have had to remove the detergent from the shelves and place it under lock and key to prevent it from being stolen.
Why does this work for the dealers?
[...]
Another point: police busts might yield some drugs, but it's much easier to deny dealing when there's no cash on the premises. And before the police figured it out, even suspiciously large amounts of detergent wouldn't have figured. So certain drug dealers would come home from getting bail to find their "money" still there!