Maybe just an awkward sales agent, or they thought you were mad at them for in their mind trying to help. I decline phone number and zip code all the time. Also been using someone else’s phone number at grocery stores for years – started by mistake. I don’t care about accumulated points or whatever but discounts at grocery store are pretty significant for me.
But I understand your frustration in general. Keep up the good fight :)
I like your idea, but it just brings to mind how fragile all of our digital media is, not to mention the surrounding tech necessary to read and understand it. What we know works is to press your message to the future, grocery bill, whatever, into clay and then accidentally burn the city down around it – good for millennia.