Regarding my recent post about being asked to type in a ZIP code when buying gas by credit card in Eastern Pa., reader Paul sent this:
I have noticed this too when travelling east of Pittsburgh. A sticker on one pump I used stressed to use my billing zip code since it was a check for stolen cards. On an trip to Burke, VA last Easter, I put in the local zip code 22015 to see what would happen. The pump cancelled the transaction. So I tried again with my home zip code and the pump responded normally.
So I guess this is a card-theft check, not just gathering info on customers.