People do realize something is happening. It’s why so many think Facebook is “listening” to their conversations then showing ads for “products I’ve never searched for then talked to about with a friend”. No, FB inferred you would buy it because your friend just did.
It’s hard to comprehend the effects of data collection. Which, of course, makes it even more powerful.
Per the story: They had purchased ice cream at the grocery store using a credit card "never used for online purchases", and then at home they see an online ad for that very brand//flavor of ice cream. This raised alarm bells, hence the post to sanity-check.
Sometimes it's like we shouldn't fear the Terminator but the access terminal in our pocket. Other times it seems like both, or neither.
The ice cream is straightforwardly due to the full purchase data being backhauled to the surveillance companies. The real wtf here is assuming that a card not being "used on the Internet" affects anything. People want to cling to this really weird "if I don't see it, it can't be happening model", as opposed to realizing that the surveillance industry is based around operating without your involvement or consent.
You're part of a cohort that the brand thinks would buy it. Or at least talk about.