Outside of the tech bubble, simply saying "yes" would be disingenuous. They're not even asking the question in the first place

I think retargeting has thoroughly blown up the idea that ads online are shown to everyone. My non-technical acquaintances are very aware of why certain products follow them around the internet in ads.

But do people assume the same thing about, say, Google search results? Promoted posts on Reddit? The ads (or natural posts) on Snapchat or Instagram?

I agree that it's pretty obvious you're being retargeted when ads for camping supplies start showing up three days after you search for them on Amazon. But the practice of "personalization" of results and ads is far larger and deeper, to a degree that most people never seem to think about.

Agreed. Although we all hate it, if my mom searches for hard sided luggage on amazon and ads for it follow her to all manner of other sites - that’s the best way for non-tech types to get some of the idea here.

The truth is WAY worse of course, but she immediately knows the ads she saw won’t show for me as well.

There's an occasional thing in UK politics where some public figure X has a go at another figure Y for having offensive ads on their website, without realising about the targeting which means the ads are driven by their own search results.

I think most people do assume the same with search results. How many do you think assume that the ads on the TV they see could be different than what the neighbor is seeing when watching the same channel with the same cable company? I think a lot of people assume that others see the same news and the way people act you'd think they assume that others see the same things in their newsfeed/timeline / facebook thing - and wonder how others could have a different view.

Even when I explain how ads can be different, I don't think people really want to believe it, or understand it, and they certainly do not realize the power of these targeting abilities..