This is done to help maintain strategic advantage for a client among its competitors. Not only do competitors not know specifically the kind of information the client has on their site users, they are not aware the client has undertaken research to obtain this information. Knowing detailed site behavior about your competition is, of course, of great strategic advantage. You know the strengths and weaknesses of your competitors and can take appropriate actions. As a result you are in a better position to increase the market share of your web site.
All data belong exclusively to the client.