At Schwab my voice is my password. Is how Schwab authenticates me by voice. That demonstrates to me schwab knows they need a voice passphrase that wouldn't be used in passing or without raising suspicion.
Finally I’m know that passphrase is tied to my phone number. Its not perfect but it is as good as any other consumer banks system.
I don’t recommend Schwab but my accounts are as secure as any.
Using just ones voice is bad. Using a phrase is better. Using a phrase that is unique and describes its function may set-off alarm bells for some.
I never connected the phrase with Sneakers.