Yes, people do it all the time and even publish many astonishing things on YouTube, BUT ... at least in Europe, with all the fuzz on dashcams in cars (forbidden in many countries and the first law suits came to public recently) and the emerging thread by camera drones, it can be expected that authorities will check these video tapings for obvious illegal actions in great style soon. It is a money machine to collect the fines connected to airspace violations and watching YT is such an easier way of surveillance ...