I don't see the relevance of the tagged post. A guy asks a question (which is not even in the same context as the OP) and another guy replies with a negative, with no supporting argument or document.
Again, we would also never submit our bank accounts to anybody right, if we follow what common sense dictates? But for this process, we even tell (CLAIM) the immigration office our bank details and the balance. We would certainly need to give them the right to access the account and verify the details. The only way for the officer to verify our claims is by cross examining. That's what a background check is.
It's very probable that a person had the sufficient amount while applying, but since the process can take up to 6 months, during this period, they may not have the funds anymore.
So when the immigration officer checks and finds that the person had claimed a certain amount, but now has only a few hundred dollars left in his account, how will they verify that the candidate can support themselves in the new country? A letter from a bank manager, dated 6 months before the immigration officer checks it is hardly sufficient.