Anonymous and untraceable, which makes them valuable in certain applications.
I am reminded of a episode in Air Force training (Sheppard AFB), where we had a guy who spent ten weeks there and had probably made over 120 Polaroid pictures of three different girls he met in that time...in various poses. He graduated the week prior to me....and his wife from Kentucky came out to pick him up. For some reason, he’d dragged down all his personal stuff...making three or four trips to the car...when the wife must have opened something to find the Polaroids. The wife didn’t say nothing, but about 30 minutes after they left base and were on the interstate...she stopped at some rest stop...and then took off for Kentucky without him. He came back to base that night. We chipped in ten bucks each and he bought a bus ticket to Kentucky the next day. Never knew what happened after that point.