Where to start:
In a cashless society, Packard will starve to death because he won't be able to buy mystery meat from his favorite corner market.
In a cashless society, Packard will become a drug mule by selling his half assed kanji characters and erotic school girl drawings for millions to cover the illicit sale of kava root.
In a cashless society, Packard doesn't know his pension fund was busted because he forgot the PIN number to his debit card.
I could go on....