Oh they definitely do this. At least the traditional loyalty-card/coupon-enabled physical targeted ads do add enough random stuff that you find it non-creepy, after they had a few high-profile cases back in the day where they started targeted advertising of baby products to teenage girls, and parents got mad. The kicker was they turned out to frequently be real cases of teen pregnancies.

I remember that, it was Target wasn't it and they inferred her pregnancy status because she started buying unscented deodorants and stopped buying sanitary products.

Funnily enough when I'm discussing the dangerous nature of large datasets in the hands of companies/bad actors (sometimes the one and the same...) and the "creepy" effects this is one of the examples I use, I've found that if you know a little about the person and couch the argument in a way they can personally respond to, they understand even if they don't know the first thing about technology generally.

EDIT: https://www.forbes.com/sites/kashmirhill/2012/02/16/how-targ... for anyone who hasn't seen it.

The have to put in some out of context ads sometimes, just so they can train their system.

For example they may show you an ads about hairdryers after you searched for computer keyboards. There is absolutely no relationship between the two, but Google doesn't know it yet, so they try. After all, there may be a correlation. In the likely event where there isn't, Google will simply stop showing hairdryer ads and show you computer mice instead (a known correlation) or running shoes (another experiment).

You'd think they'd sprinkle in something less ... annoyingly skewed that obscure what I actually want to see.