It is indeed useful when that rejection gives a built-in way of moving your business to another bank that’s less reckless with excessive data collection.

But it does not always work out that way. I refused to answer a needless intrusive interrogation and it had no effect (which also proves the interrogation was not necessary). The bank likely made a note of my refusal… perhaps to try to use against me. They really want you to believe you’re required to answer those questions. In any case, it obviously makes sense to avoid the banks that show signs of over-collection because it hints that there could be more excessive collections going on with that bank. E.g. when you call the bank, some banks will initiate a spontaneous interrogation unrelated to the reason for your call.

There are countless ethical reasons to do as many transactions in cash as possible. If a bank were to show me the door for doing too many withdrawals, then it would actually be a feature. You don’t want your money in a bank who is protectionist against runs on the bank. It’s better to bank where your money is not trapped.