At times these devices are EVIL
A couple of points:
If the pilot can see the ground (airport/runway), then the idiot with the laser pointer can "see" him.
The pointers do spread out a bit, but not that much. The "aimer" (idiot on ground) usually uses a reflection on the windscreen to aim.
While driving on the freeway a couple of years ago (at night!) I had one of these pointed at me. It was VERY distracting, especially since you really don't know what it is, and it is very unexpected).
Everyone should try to drive into the blinding setting sun to have a similar effect. You end up lowering visors, putting up hands, moving papers, anything to get it out of the way. Now do that while landing a plane. Oh wait you weren't told about it in advance.
Counter measures (zapping back) might cure the problem (permanently!).
Oh, another thing, the wavelength (green) is where the eye is most sensitive (so we can tell different vegetation apart from the tasty animals we used to hunt).