It may also be a measure of the level of unmanned Ops. Let's face it, not having to supply a life support infrastructure aboard does free up a lot of weight and real estate.
For jobs requiring long loiter times, they're ideal. So some will go down, tell me that doesn't happen in manned flight.
Obviously there is also a Duty of Care in their operation, but they are a PART of the future of military and/or security operations.