There are people of interest identified by companies. Most consumers fit into a generic bucket where their data is largely ignored - other than to serve them more relevant advertisements - to get them to buy more products. There are some people, however, that are flagged in special tables or possibly brand new databases.
These companies identify persons of interest by analyzing all of their data. I imagine there is a "sweet spot" range of anomalousness that a person has to be in to be flagged as more "track-worthy" than the average consumer.
These companies have the ability to manipulate these people with even more targeted advertising and other methods on a honed in, micro-scale.
What is the goal? What do the companies hope to gain from analyzing these specifically selected people?