Can't you also opt out giving them your ss#?

In Canada, the Social Insurance Number (a similar nine-digit number for everybody) is always OPTIONAL by law on anything but employment applications and dealing with tax authorities. The bureaus always ask for it, but in fine print it always must say "optional." They say they need it for cross-checking, but they ask for other pieces of ID so they can just use that instead.

I like the idea of a, say, a 6 to eight digit pin number assigned to all who need access to credit files. After all, I bank at ATMs and online with only a PIN number and ID number. And these institutions know MORE about me in some cases than the bureau!