When people are using the paper notes for paying for stuff.. Almost non of the users understands how new paper notes are issued or why and how different stuff have a price.

When people are using the plastic cards almost non of the users understand how it works, they don't understans the cryptographic algorithms which protects the credentials for your payment information which the merchants system pass up streams, almost non of the user understands that visa/mastercard never touched their money but takes a fee anyway.

There is so many things in the society which people using everyday but have no clue about how it works and why. They just accept it because it is more convenient to use it than the alternatives.