Disgust aside, what would give them the legal right to do this? Is this covered by the TOS of the Facebook android app? If this is just plainly legal without

Disgust aside, what would give them the legal right to do this? Is this covered by the TOS of the Facebook android app? If this is just plainly legal without even the fig-leaf of a TOS, why do we even have the 4th and 5th amendment at all? It's routine for intel/police agencies to purchase ad profiles of citizens, why bother with any fancy NSA super-surveillance when you can just buy an entire history of private conversations and behavioral data from CMG or any other advertiser.