I wish my government was asking people to be careful buying weed.

Instead they prefer the "don't buy weed! you'll be an addict, lose everything, go to prison, detox, maybe you'll die die, or be a homeless hobo living under a bridge".
As long as nothing beats cash's current main utility as a fungible form of money, people will keep using it.
Of course! I prefer to use cash than electronic payments, simply because everyone accepts it. There are stores with no terminals, or no Internet, but there are no stores that won't take a paper bill. Also, I've come to appreciate cash when dealing with contractors on various properties. Most of them will accept only cash, because you can't expect a plumber or electrician to have a card terminal. Some do, but most don't. My dentist only accepts cash because she doesn't want to pay the fees for card transactions.