"Does dropping (malicious) USB drives in parking lots and other places really work?"
297 samples were dropped, 290 got picked up. 135 people opened documents (HTML pinger), 54 flash drives got returned.
20% were opened within the first hour. In less than 5 hours half of the devices were used by someone.
Study & talk (2016) by Elie Bursztein: https://www.youtube.com/watch?v=XJCQBqTmGUU