I finally figured out the spookiness after talking to my mom on the phone about vacuum cleaners and then getting ads for vacuum cleaners:

My mom bought a vacuum online after our phone call, and one way advertisers choose an audience is “all the friends of someone who searched for the product”

My roommate and I confirmed this by getting ads for something the other just googled.

What I’m trying to say is, targeted ads ruin Christmas, but no one will hear me out :’(