The info collected helps them detect unusual activity in your account usage. Its quite helpful for fraud detection. Same as if you never buy say cars with your card but then suddenly one day you, it will get flagged on the spot because its not part of your normal usage profile.
Always try to remember the banks dislike government and the ATO even more than you do. They like you because your making them money.
That's the thing. At what point do you value privacy over security? What we get today is increases in convenience, which leads to a decrease in security, and to combat that decrease in security, they also decrease your privacy...
Banks only care about profits (and power) and the effort + expenditure to make said profits. Their dislike for the government and the ATO is solely based on those entities impeding on their ability to make profits. As you said, they only like me because I do, or have the potential to, make them $$.
The increase in "security" is not to help me, helping me is a byproduct of helping themselves - all at the expense of my privacy.
I don't appreciate the erosions of my privacy AND the way they try to sell it to me as added security.
I wouldn't give you or anyone else unfettered access my personal information, bank statements, location, what device I'm using OR it's operating system. I don't appreciate this becoming the new normal and believe it's an important area to be concerned about.
As Edward Snowden once said:
"Saying you don't care about your privacy because you've got nothing to hide, is like saying you don't care about freedom of speech because you've got nothing to say".
Give 'em an inch and they'll take a mile! This is a wide spread problem that I believe more people need to become concerned with. I don't forget that these entities are still just comprised of individuals serving the interests of other individuals. Privacy is an integral part of our individual freedoms and I don't take my personal freedoms lightly.