I have not heard any of this firsthand, but someone just sent me a link to this LI post. Is this old news, or a new thing?
Presumably it's not for everyone in the whole zip code- do they do a soft pull first and combine what's on your credit report with the zip code that you live in? (It's certainly possible that this guy has opened/closed cards with other banks.)
Or have they simply flagged this guy's address due to other people at that address churning Amex cards?