They're trivial to deploy - a child could do it if you showed them once. If you can afford to lose one being knocked out of the sky, you still draw attention by

They're trivial to deploy - a child could do it if you showed them once. If you can afford to lose one being knocked out of the sky, you still draw attention by returning to ground every 20-30 minutes to swap batteries. Batteries are $100-200 each, at least for the drones I have, so not really something that a casual protester would be carrying around. Battery packs that can recharge drone batteries are heavy, expensive and uncommon. If police/NG are firing projectiles at journalists, grocery shoppers and people in their front yard, I can imagine they'd be delighted to play target practice with a drone. You could be high enough that no one would notice, but then you're not going to get especially useful video. Low light situations wouldn't help. A racing drone would be more difficult to control (AFAIK, no hover or GPS-based positioning) in trying to film specific things for 20 minutes at a time. If you wanted to film with a touch of elevation over a crowd, you'd carry a GoPro on a stick. Cheaper, cheaper batteries, can charge via USB with any battery pack.