The problem with this is that Bernie is mostly interested in money, and his primary skillset is that of a dealmaker. For a dealmaker like him, having walking away being considered "unthinkable" is a major problem. If you can't walk away, how do you negotiate a better deal? You don't have any leverage if you can't walk away. So Bernie has to do a whole bunch of "unthinkable" things just to prove that he can.
This is, of course, totally messed up. But it's where we are.