More checks at the pump

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.