Comment by georgyo

You can invest the money, the same as banks do. It's why they don't charge you to store money with them, especially if your balance is high.

You only need and should keep enough liquid cash needed to handle day to day withdrawals. Everything else is fair game up invest.

See: https://en.m.wikipedia.org/wiki/Fractional-reserve_banking

https://en.m.wikipedia.org/wiki/Bank_run