Even if someone can successfully go "off the grid" never using a cellphone or computer, and paying for everything with cash you keep stuffed under your mattress, mentions of your name and images of you will inevitably appear in others' emails, Facebook posts, and whatever else.

In addition, eventually with facial recognition and the high density of security cameras, going anywhere other than the middle of the nowhere will be building a database of your movements.

This is all more than enough to build an accurate profile of you.