(AP Photo/Julie Jacobson) Why do merchants sometimes ask us for our ZIP code when we buy something? I recently visited the Mob Museum in Las Vegas, an interesting addition to Sin City’s ...

You can't buy a pair of pants without a clerk asking for your ZIP. It turns out stores can do a lot with those five digits, and most of it isn't good.

The high court unanimously ruled last week that a ZIP code is part of a customers' address, and a state consumer privacy law forbids stores from requiring addresses during credit card transactions.

Recently I wrote an article about why so many stores ask for your ZIP code at check-out. With your name and ZIP they can turn to outside data brokers to learn your address, phone number and email ...