The trouble is, if it was pointed out to them the hazards of training in uninhabited areas, over the sea etc (engine failure, mechanical problem etc), then the antis would have more ammunition to say that helicopters are dangerous.
Groups like this never listen to reason, they have a bee in their bonnet and, if they successfully campaigned against one thing and "got it banned", they would have to turn their attention to something else.
Cheers
Whirls