> Where do you think banks got the idea? They just copied an existing shady business model.

Tracking user input methods is not a shady business model. I was doing this for web forms back in 2003/4 to fight fraud, improve the user experience, and find problems.

> If my boss got a contract with a bank that said I had to track users against their will

But they aren't being tracked against their will, so you would have done this.