This is not necessarily true either. Don't forget that every time your "90%" scenario happens there is some fixed asset attached to back up the loan. The new money doesn't come from nowhere.
Banks loan out a certain portion of deposits (your examples are 90% but that is hardly true in the real world). It is supposed to make those loans with a lean on the property that the loan is written for, and they are supposed to follow standards so that the property value will not fall below the loan amount.
So no depositor money is lost unless the property (a house for example) falls below the value of the loan and for whatever reason the bank needs to sell.
The major fraud of the last few years is not simply the fact that 90% of deposits can be loaned. The fraud is when those 90% are loaned out to shady borrowers for shady assets with complete disregard for the risk of losing the depositors' money.
The bigger fraud is that this is a 'suprise'. That bank runs/failures are 'unnatural'. The Recessions 'shouldn't' happen.
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