Is it? The airport is forced to block all flights, which in turn prevents danger to passengers. That's the whole purpose behind the drones.
This causes disruption to not just one airport but many. Diverting planes and generally making a mess of flight plans is most definitely putting lives in danger.
It also causes more people to drive, which will cause more people to die. When’s the last time a person was killed on an airplane in the UK - Lockerbie?
Is planning a bomb ok if you phone in a warning before hand so that the building gets evacuated?