> And, just as importantly, can joe/jane user do it?

Irrelevant as those users will not care and just punch in their credit card if asked.

If by 'form of store' you mean the official Apple store; yes. I've never purchased a single thing from Apple's 'app store' (and don't really plan to). Everything I've needed so far is free.

The identity part? I have an account, so yes, some sort of 'identity' is revealed, but that doesn't relate to the credit card part.

They still do not know a thing about any of my credit cards, from initial setup to everyday use.