Banks traditionally benefit when their borrowers do well.
You take the customer to the hoops and pucks and you get him laid, and he pays you another two points. I'm the wizard from New York. The extent to which these information advantages could be exploited at the highest levels of the banking industry was horrifyingly revealed in 1994, when Bankers Trust consented to findings by the Securities and Exchange Commission and the Commodity Futures Trading Commission that it had lied to and cheated Gibson Greeting Cards in a series of transactions from November 1991 through March 1994. All these involved correlations between interest rates for different maturities of Treasury instruments, interest rates in the London dollar-denominated interbank market, and so forth. The procedure for calculating the value of the deal was so complicated that it existed only in the form of a computer program.