You can park your money safely anyway, just buy a vault. There are even specialized bank accounts where they just store you money and don't lend it out.

However, you won't earn any interest, and thus will lose opportunity cost and also lose value as cash inflates.

Additionally, the money that banks lend is critical to the economy - which includes your job and the general welfare - like water to a person. If banks stop lending - if all that money gets put in a vault - businesses and citizes lose access to money to develop things and we get talented people and valuable resources sitting dormant, a depression.