In a few stores here in Australia, I am asked for my post code (or country of residence if no post code) by the cashier when ringing up a sale. Predominantly at tourist/tour related points of sale, but I've also had it an electronics and white goods stores.
No idea if the operator is also recording gender and perceived age group etc., but I do know that on most occasions, you can opt not to answer the post code question.
When you go to those weekend open inspections in Sydney, you are almost guaranteed to be asked for your postcode. They record that as well.
I actually did some experiments - for different properties in roughly the same area/price range, I told different real estate agents different postcodes. It is beyond reasonable doubt that the code you tell them play a huge role on how they rank you as potential buyers. When you tell them a random north shore post code, you are guaranteed to receive a nice & friendly follow up on the coming Monday, however if you tell them that you live in the west (when mostly inspecting north shore properties), they would smile and immediately end the whole conversation.
The sample size here is ~50, which I believe is big enough to draw some reasonable conclusions.
Buying data lists. You usee your mobile number to get your cinema ticket - or whatever - the cinema sells that data. Do you get package alerts when you have a parcel due, now your phone number is joined to that address, plus presumably the credit card companies sell their data (?).
Companies amalgamate that data, then sell lookups of varying degrees.
Screwfix in the UK gather a lot of personal data as part of their sales process, they're the least covert about data gathering I've seen.
I'm not sure if it's true, but a friend once told me the reason a store asked for your zip code was to see if they had a large audience coming from a certain area. This let them know other locations to possibly open other stores.
As far back as 2000, my partner was asked for her zip code as we made a purchase and I curtly replied "no comment," to the surprise of everyone there. She walked for her phone number, which really irritated me because this was a $5 retail purchase of some type), and I got more curt when I said, "You don't need that!"
I've been annoyed by this stuff long before most people were ready to consider privacy concerns anything more than paranoia.
I like to give fake numbers in these situations. The way I see it, intentionally supplying bogus data is one of the only ways we have left to fight the machines and their algorithms!
I like to give obviously fake numbers. Like 12345 for a zip code or 212-555-1234 for a phone number. Most people don't care enough to have a reaction, now and then you get a laugh, and rarely you'll get someone who calls it out as bogus. My standard retort is somewhere between "Are you saying I don't know my own phone number?" and "Are you calling a liar?!" depending on how surly the response.
I was in an albertsons back when they wanted a number in tahoe and went in the 2nd time... cashier remembered me and said "what's that number again... something something something 5309eynine..." and was dancing a bit... it took me a second then I said "what's the area code here?" he glady gave it to me, so for about 12 years I just did $CURRENT_ZIP-867-5309.
My safeway card is in someone else's name... one day they had to pull it for some reason and I got a "Have a nice day.... Mr.... Soprano." and a big smile.
My father had memorized a fake Social Security Number that had come as a sample card in a wallet he got in the 1950s. When anybody except the government asked for his SSN and who wouldn't relent on his pushback, he would give them that number.
Wow, nice! I don't know if he was one of the 12 in 1977, but he would have been if this is the number he used. Woolworth's totally makes sense. If he were alive, he would poop purple Twinkies at that story. Thanks!
He's been dead for 10 years, but he didn't use it for those. As I remember it, in the 80s-90s it was more common for SSNs to be requested for normal consumer things.
I gotta say, it's possible he never actually used it in my lifetime, but he could sure tell that story and rattle off the digits at a moment's prompting.
There's a bit of plausible deniability if you give slightly bogus info, like transposing numbers. You could assert that there was a typo on the company's part.
Sometimes the credit card terminal will ask especially at gas pumps for my zip code as an anti fraud measure, and will reject the transaction of you enter the wrong number.
If a cashier is asking I always use 90210.
I guess a lot of people not from the US will use 90210 when prompted for a US postal code. I can't even remember what the show was about (except that it was set in Beverly Hills, obviously), but the number stuck.
I had same issue when visiting the US. I tried some fake numbers but it wouldn't accept it (my actual postal code has letters, so that wasn't possible), so I just ended up paying by cash.
Post codes in Australia are just 4 numbers, so when buying subway tickets in NYC, I just put in 10000 or something (I believe that's close enough to the local code?).
Not necessary, most point of sale systems can provide a unique hashed or tokenized version of the account number for analytics and identification purposes.
By cross-referencing your name (from your credit/debit card) with your zip/post-code, stores are able to determine specifically who you are with greater probability than without the zip/post-code.
Seriously, I mostly shop in the same neighbourhoods. And when not, there's often something on the counter with their address...or I can give a mate's address and let him get the junk mail....
No idea if the operator is also recording gender and perceived age group etc., but I do know that on most occasions, you can opt not to answer the post code question.