It's true that it never really existed, yes. But as long as people thought it existed, it had great effect. That's the way it is with things of that sort. More of it is being created out of thin air at this very moment, and you can buy stuff with it if it's put in your name.

For instance: Do you need $30 million? Do you move in the kind of circles where that sort of sum changes hands regularly? Can you provide some sort of collateral?

If so, then a major bank will lend you the $30 million and charge you interest for it. They don't go to a vault and pick up a REAL $30 million in government-issued paper money, coins, bullion, or anything else like that. They just write up a loan agreement which you and they sign....and a computer keystroke magically creates a new $30 million which gets deposited into your account. It came from nowhere...but now it's considered REAL! You owe it to the bank which just created it out of nothing. ;-) And it earns interest, which means that even more money must come from somewhere to pay the bank.

That's a pyramid scheme. It's fraud, in fact. Banks can do it legally. Therein lies the essential problem, and that's why bankers are so rich.