Shocking! Abuse of power and shady tracking techniques by Facebook? Unheard of! Seriously, this cannot be surprising after learning that the Messenger app listens to everything you do, all the time. That's just off the top of my head. They are doing this and much more.
I've heard a lot of anecdotal reports of the messenger app listening to what you do. So much so that I've uninstalled the app. However, I've never seen a non-anecdotal source or even a source that gathers all anecdotes and gives a decent meta-analysis. Would you happen to have one?
The messenger app probably doesn’t listen to you, but it’s abusive in other ways and shouldn’t be uninstalled. The main creepy feature of Facebook apps is that they continuously track your location. That’s a source of much of the creepy targeting that people notice.
Also, Facebook’s weasel-worded response to the issue implies that they do not use pervasive audio targeting, but buy data from people who do. The Wired article that claimed that using audio was impractical is nonsense.