There are so many possibilities here. There is the stores you visited and the Credit card company involved along with anyone of the ad tech partners who have a

There are so many possibilities here. There is the stores you visited and the Credit card company involved along with anyone of the ad tech partners who have a cookie on you tied to your email. Now how they know you bought X 1. Say CC sells data to say Bluekai (now salesforce). If you bought a hammer, they need not have known it was from HD, a middle man might simply be bidding for anyone categorized as shopping for home improvement goods and hoping to cash in on HD lead-gen/affiliate $$$ 2. You likely searched online for these at some site and probably just don’t remember that you did. The only thing that will get rid of this is to ban/regulate “affiliate” marketing (so shady companies who don’t follow rules can’t cash in), because so long as someone is willing to pay to bring sales, it will happen on way or another.