I am pretty well connected, I retired from the Air Force and am now a consultant for multiple government agencies and other nations who are building their drone capabilities.
Honestly, 90% is retarded people who see a light in the sky and scream drone. It's largely idiots who know fuck all about this topic. The other 10% is a mix of hobbiests doing illegal shit, likely some espionage (like the dude in cali who was arrested), and people doing nefarious shit. What its not is fucking aliens.
I do a lot of weird shit with drones for a job and most people don't notice, then someone does and they start freaking out and it gets blown out of proportion. I work Group 1-5 drones, counter drone, and niche/future capabilities and it's retarded to use a group <3 to do nuclear detection, there's fixed wing manned aircraft that do it far better and far cheaper.