You take a picture on the beach and catch me in the frame, I'm totally fine with that, you take pictures of that beach every day for a year and then put IDs on every 'face' so that you've got a history of everyone who has been to the beach, I'm much less comfortable with that, you create an API so that someone can send you a picture of a face and you will give them the history of that face at the beach for the last 12 months, I've got a huge problem with that.