When you say "Although the traditional currency is inconvenient, it is difficult to encounter fraud..." I am not sure what you mean. Our prisons are filled with thieves of all stripes. Cash brings out all sorts of scams and mayhem. Not to mention it is the tool of trade for drug dealers. While there have been some epic hacks of crypto currencies, I am not worried because a general in Nigeria has six million dollars in gold and he just needs my banking information so he can transfer it to me and I get to keep half. I just got his email today. (Just a joke friend, but you get my point.)