Money in their vaults? LMFAO
How can you believe that banks still keep "money" in their "vaults"? Or was that a figure of speech intended to simplify things for those who think that people's savings are used to create loans.
When banks get deposits they invest them to so they can make some profit and pay the interest due to the investor, yes. But when they create loans they just write the amount of the loan into the borrower's account. They used to have to actually deduct some percentage of the loan (usually 10%) from their balance sheet (google Fractional Reserve banking). But thanks to Gordy removing the reserve requirements, even high-street banks can create money out of nothing, lend it out and then have the cheek to demand interest on it. Interest is intended to compensate the lender for loss of investment opportunity. But if the money didn't exist until it was loaned, where's the loss?
And where does the borrower get the extra money to pay the interest on the loan? Well, if you follow it for long enough it can only come from another loan, made to somebody else. Which in turn requires interest. So the whole system* creates poverty by design as there can never be enough new money created for everybody to pay off their loans, so some people always default and the bank takes their house / business to sell off.
It only works because most people don't know how it works. Somebody will come along in a minute to declare that the above is all just a conspiracy theory and everything's fine.
* The banking system, not capitalism.