Instead of paper money for you will exist only the login and password of the account, with which operations will be performed. Or in general, just come and present your unique body parts: finger, eye, etc. Even a card is not necessary, because it is only needed so that the seller can make sure that the account with which he withdraws money is yours.
Already there are bills that can be used to substitute a special device for reading the retina of the eye.
I think this is the future. It is enough to supply all the places of sale (shops, clubs, cinemas) with personal identification devices, and the need for paper money will disappear. Came, you identified and withdrawn from the account the right amount. And also arrange for all cities a special scoreboard, where you can find out the balance of your account by intensifying yourself. And at the same time and pay for any services (phone, rent, credit, etc.). All this really exists, just not yet very widespread.
That's too much work and security. Using the eye as a security still has flaws since you can get into accidents. When you get to an accident and lost your eyes, then you can't use your money anymore. I've never seen anything like that except from the movies. Perhaps that's where that idea came from?
Fiat has been used by everyone for so long not because it's secure but because it's easy to use. It has a physical form so you simply hand it over to the guy you're transacting with. No verification or identity required at all. Some people don't like too much verification and identification. They want their transactions to be more confidential.