Ask HN: Talked about my fave cereals now I see ads for the exact cereals. How?

I was talking to my family meme bees about my top five cereals. (Reese’s puffs, Cap’n Crunch etc) I open up Twitter about an hour later and I see ads for those two exact cereals. I never searched for anything but even if I did and don’t remember my search engine is ddg.

There was a tlc Roku tv (which I’m connected to for remote control) and my iPhone, that’s it.

How the hell did I get these ads? I’ve never got a cereal ad before.