Exactly, their predictive algorithms are entirely too accurate and it’s not just clicking on or searching for products that gives them the information. Even how long it took you to scroll past something is used to analyze potential future behavior and deliver you ads.
You take in so much content everyday that you don’t even realize. They probably saw plenty of them that OP didn’t even realize, I’m sure they gave it away via some other means.
People have tested this before and gotten no additional ads based on their words, it’s all anecdotal.