I really wonder why nobody did use an off the shelf high payload drone, e.g. an octocopter, to attack a drone pilot on its way home, at home, at the football ma

I really wonder why nobody did use an off the shelf high payload drone, e.g. an octocopter, to attack a drone pilot on its way home, at home, at the football match, or when he picks up his children from school. Those drone pilots are combatants and therefore legal targets of war, regardless how deep they hide in the hinterland. I don't think that Pakistan will declare war to US. The relation is totally odd, with US financing Pakistan military on one side, while bombing those parts where Pakistan lost control on the other hand side. Pakistan and US are close allies, who both know that staying allies is the best they can do. But some self declared Islamic state might do. Its just retaliation from their viewpoint. And that kind of attack is plain cheap to execute, would perfectly fit into the picture of an asymmetrical war, and even be legal as drone pilots are combatants. So I really wonder, why nobody did so far.