99+% of every single person you meet has either FB, IG or WA installed on their phones and shares their phonebooks with them (assuming you live in [insert western country here]). There is also a very big chance at least some have your full name and address in their phonebook. Facebook not only knows who you are, but also who you are in contact with, when you meet new people and who they are. They also collect phone and text records with their apps so they also know the frequency that you have contact with them and they can even read the content of text messages (most people these permissions to the apps because it will automatically verify the associated phone number). Add all the location data, ssid/mac address collection and countless of other datapoints to it and they can draw out your entire life even when you don't use anything from facebook. There is no escape.