Discharging a firearm into the sky isn't it. I don't know if I'd classify this as being as bad as shooting at a passenger plane, but the gun probably won't hit a plane 30k ft in the sky anyway, and the missed bullets/pellets (when you inevitably miss the plane or drone) will almost certainly kill someone if they fall on their head. I'd be disappointed if there wasn't a felony charge for doing that.
Whether the drones should be allowed is another question of course, but the potential collateral here can't just be brushed off.