Oh right, the following mode! Hadn't thought of that, that surely counts as flying by camera. But it doesn't apply to the situation where you give the drone a preconfigured, uh, visual coordinates (a path, I guess that must be?) and it will try to follow it. So it still cannot wreak havoc at an airport without either you being there (follow mode), GPS being available (autopilot to coordinates), or flying manually using a remote control.