Read "The Used Car Salesman Defense" section in this issue of Matt Levine's "Money Stuff": https://www.bloomberg.com/view/articles/2018-03-20/explainin...

It boils down to this: "Banks are always trying to get customers to think of them as trusted agents, while reserving the right to act as rapacious counterparties."

I like Matt Levine because his "I was on the inside" voice is pragmatic and straightforward, and often makes me stop and say, "Huh."