to make a drone cheap they use cameras instead of LIDAR

Can't use LIDAR in most military applications not due to cost but because it makes your vehicles and drones into a beacon that can be seen for miles through not just infrared optics but even shitty digital cameras. Most people don't realize this unless they live somewhere companies are testing self driving cars and sidewalk delivery robots. First time you see them on digital security camera, it's a real "wtf is that" moment.

check out this security camera footage: https://youtube.com/watch?v=uOWPj-4SSTU

You don't notice this with the naked eye because LIDAR systems all have their lasers tuned to the near-infrared spectrum (like an ir TV remote) but with a standard CMOS camera sensor it looks like the vehicle has a lighthouse installed on it. With smart phone cameras made in the last 7 or so years because they added a filter to remove it so people's pictures/video don't get randomly fkd up.