The economies of scope, deriving from the need to provide trading, clearing and settlement services in a sequential way, can be fully exploited in case of vertical integration of the various infrastructure used in the value chain of a securities transaction.
Is it ethical to impose inordinately high charges and fees? I am sure you know the right answer. Is it not ethical for banks to supply their customers with information about the charges and fees? All in all, the culture of any bank does matter.