This is similar to the story of the guy who pranked his roommate by buying Facebook targeted ads that only targeted him [0]. Perhaps in the future, the AIs will know us all so well that every interaction will be filled with little in-jokes.
There is an update. He mentions that they restricted to minimum of 20 people, but there is a loophole, because you can select criteria on that group.
He gives example that if your want to target a guy friend, you can create a group of 1 male and 19 female friends and then create ad targeting just males to get around it.
The fact that you can do this make me very paranoid. I am so glad I don't use facebook. I'm pretty sure with the rise of face recognition, object recognition and NLP you can create insanely targeted ads that are almost ransomware by crawling people's social profiles and correlating them with hacked datasets.
How is this different from the ability to send someone an email? I just don't understand the concern of being able to send ads to one person other than "random non-technical people will not expect that and think it is a ghost".
I don't know how precise the ad targeting exactly, but what if you narrow the base group down to your 19 fake accounts and your target user.
If you could the further filter your ad based on gender (as mentioned above), personal interests or other private data, you may be able to use your ad impressions to figure out things about an unsuspecting person.
I saw a demo of an app using Microsoft's Computer Vision api that would figure out your demographics from facial recognition and show you ads targeted to your demographic.
Facebook has removed the ability to make such narrow target groups.