It's not uncommon for a store to ask for a customer's zip code during a transaction or return, and for most of us, we have no problem giving it. How could giving out a simple five digit number pose any sort of privacy risk when there are thousands of other people living and working in the same zip code?
Consider this a signal boost—according to a new report in Forbes, quite a bit. As contributor Adam Tanner writes:
...along with other information, the ZIP code may provide the final clue to figuring out your address, phone number and past purchasing details, if a sales clerk sees your name while swiping your credit card.
How does this work? In one of their brochures, direct marketing services company Harte-Hanks describes the GeoCapture service they offer retail businesses as follows: “Users simply capture name from the credit card swipe and request a customer’s ZIP code during the transaction. GeoCapture matches the collected information to a comprehensive consumer database to return an address.” In a promotional brochure, they claim accuracy rates as high as 100%.
Yikes. While some may be comfortable giving out a five-digit zipcode that just gives a general idea of where they live, it's safe to assume most would not be OK with a store acquiring their entire address without their knowledge.
He also shares a story about a California woman named Jo Anna Davis who, as a victim of domestic abuse who works as a counselor for other victims, guards her privacy fiercely. According to Davis, when she once attempted to return an item at the beauty store Ulta, the clerk asked her for her zip code--and when she refused to give it, the clerk called over the manager, who gave her trouble for not disclosing her zip code and refused to give her the receipt back. Davis then took the receipt and attempted to leave the store, but the manager then locked the doors and demanded she return the receipt. All this, over a zip code.
It really all comes back to our right to privacy. Recent revelations about the NSA's surveillance program have made the debate about how secure our personal information really is, and though marketing data isn't the same as phone and email conversations being potentially spied on, it's still in the same vein: We all still have our rights, and it's important to know what they are for any situation.
For instance: As Tanner points out in the article, the California Supreme Court ruled in 2011 that stores cannot require customers to disclose their zip code if they do not want to in the state of CA. Massachusetts ruled the same thing earlier this year, becoming the second state to do so.
Of course, not all requests for zip codes are going to be used to pinpoint the exact address and contact information of customers—that requires a firm like the aforementioned Harte-Hanks, and companies have to pay money for that—but you can still deny to give it out if you don't want to. Or, if just use a generic zip code for purchases, or your work's zip code.