We have unofficially incorporated drones into our roof inspections. And this is exactly the kind of thing we can find that you would otherwise not see from the ground (rust on the chimney cap). It also makes it safer for us inspectors to not have to get on these steep (re: unsafe) roofs.
Our infrared camera discovered the builder forgot to have the hole cut out for the supply vent from the HVAC system. We were running the cooling mode and then saw in the thermal image that there was an unusual cold spot (blue) that should not otherwise be there. Whoops!