Knowing your customer

[Nomen Nescio]

R. A. Hettinga wrote:

> Duncan Frissell popped up here on cypherpunks with pointers to the odd
> bank in South Dakota or somewhere, 4 or 5 years ago, where you could get
> a bank account without a SSN. It was exceptional in its example, and I
> would doubt it possible even now.

...

Has anyone recently attempted to open a non-interest bearing checking
account without giving out an SSAN?

What possible rationale (aside from "bank policy," "identification when
you lose your passbook," "it's easier for us this way," or "the computer
won't let us do that") could a bank (or the fedgov) have for requiring
social security account numbers on such accounts?