I say potentially because I can’t know for sure.
In the past I didn’t own a cell phone for a few years, drove a car from the early 90’s, had my debit card turned off and for over a year and exclusively used cash. I started buying fish sticks religiously as easy food for several months. I was buying the same big global brand each time. It’s not something I’ve ever bought in the previous 6 years. I would purchase them at a rural grocery store (that has not kept up with technology) using cash. I was boycotting wa ll ma rt, though I have shopped their many times in the past. One time in a pinch I did go in to w. mart and bought a different fish stick brand using cash at the self check out. Within that same month I received an ad from FB for the big global brand of fish sticks (a competitor of the one I had bought at w. mart, and the same brand I was buying at the rural grocery store) I usually pay attention to the ads I get on FB and to my “not perfect recollection” I had not received an ad for that brand before or for fish sticks in general.
I use a fake name and email on FB but had to submit them my real name once and it’s otherwise and accurate depiction of my life with real photos and friends.
I assumed at the time I was not leaving a very big digital foot print and yet coincidentally, FB linked a product I was uniquely and frequently buying at the time. My thought was that maybe it was done though facial recognition at the self check out. There was a class action law suite in IL (not where I live) against wa ll ma rt and there alleged use of clear view (In IL its illegal to sell bio metrics data), I never checked with the out come of that was.
With in this same time period the same thing happened again only with natural bread and I was given an ad for a competitors natural bread. I have bought that bread in the past and don’t remember receiving or not, ads about it so it stands out less then the fish stick experience.