FBI asks public for help with new drone sightings in New Jersey (youtube.com)
Is this to flush out people who have or use drones to monitor other drones? Or to test what locations have what noticeable effects on citizens?

If this is Chinese, it illustrates how much easier it is for China to do in the US, than for US to do in China where relatively few non-Chinese people live and where tracking is even harsher. Chinese have been arrested for flying drones to get aerial info in the US, but would they really use such large drones and make them so obvious, and do it repeatedly knowing the US was on alert to this? Then is it more likely it is a US agency or (perhaps again quite unlikely) an ally that the US can't say anything about?

Or is it a pretense to gain approval for a drone surveillance fleet for authorities in these states?

Why can't people just organize on a FacebookGroup to use their personal drones in relay to follow these craft back to their landing spots? I don't understand why this hasn't already happened?

There are countries where flying drones is illegal. Presumably, people don't want random strangers flying over their property or them at a beach or whatever, recording them, and they can't know who the stranger is, what they're doing, or follow the drone back to it's source.

Maybe the best law for drones is only allowed at designated drone parks.