I don't think they consider it "basic" from the consumer's POV. This is something you'd never be likely to hear about if you don't know someone like me, who has to deal with the credit-card companies directly. And it doesn't surprise me that Forbes would not reveal something about the merchant side of the credit-card agreement in a consumer article. It's... how do I put this... not relevant to the thrust of the article, which is "companies use your zip code for targeted advertising". And yes, a lot of them do.