There's this guy you know.
He follows you around all over town. He goes into the bars and dance clubs and tells all the creepy guys who are offering you drinks, cocaine and other dubious lures to get you to go home with them your "real" name and address, because all you gave to those guys is a first name you invented (Trixie from Poughkeepsie) to keep you safe from predators.
He roots through your trash to gather receipts like A.J. Weberman rooting through Dylan's trash, assembling a profile on what you read, your Tampax purchases, ATM receipts, frequency of bowel movements.
He lurks beneath your windows, trying to catch a glimpse of you naked in the shower, or relaxing by the fire. He collects your discarded clothing. He even saves your used Kleenexes.
He badgers your friends, wife or husband for more information. He keeps track of your bank deposits, what movies you watch, what records you listen to. He analyses everything you write for "clues" to your "inner nature."
He does this as some professed "I love you!" thing. He makes up logical reasons for such behaviour and self-justifies it. He explains he just "wants you to be safe" and "he's looking out for you" and "it's all harmless anyway."
In physical life, we call such people stalkers. They are creepy. We are even warned about them over and over by "the authorities." There's laws against this sort of behaviour.
So... what's the difference between aggressive data aggregation and stalking? Tough call...