Anonymity breeds entitlement and entitlement leads to intrusion -- a form of digital assault or harassment. Yes, AirDrop can be set to "Receiving Off" or "Contacts Only" but that isn't your point. Your point -- as I understand it -- is bigger. Why should you (or anyone) be subjected to being bothered, annoyed, threatened or worse by a total stranger? Sadly, digital empowerment (in the absence of socializing constraints) is the bane of life in the 21st Century.