The B'stards even do it on Tizen
Luckily only over WiFi not mobiledata. Until I sat on my Tizen Z3 and killed it, it used to download 13 MB of FBmessenger each day. In spite of it being standard practice to check if a new version is available by comparing against the currently installed version, it appears that the Tizen version of FBmessenger downloads and re-installs itself every day.
"By having Facebook apps pre-installed, we ensure people have the latest version of the application installed on their device, giving them access to bug fixes, critical security enhancements, and other new product features." --- what a load of B***cks! If they want to ensure you have the best user experience, they don't waste your data and processing cycles running and downloading stuff you are never going to use. If they want to do what they claim they should do the download the first time you are stupid enough to use their product.