This could be a severe national security problem if the drones sent back the video to DJI as well, then a foreign power would get geotagged high detail video of areas of the part of SF you flew over, VERY useful to a foreign intelligence service.
And I am not just talking about your drone and your flight, all other people who own and fly drones in the area would also supply data to sutch a system.
I am not saying that this is what they are doing, but please remember that the Brittish government asked the public to send in their holliday photos of the coast of France to help them plan the D-Day invasions. This kind of information is useful.