Because you are not giving free kp, you are fishing for free chests and kp. If that annoys you then stop giving. And you are not the only one.
If you do not want us fishing, then make it unattractive to fish.
there are several ways you can deal with it, you can remove the fish from the public pond (read ask your fellows to help you fill the chests so there is nothing to get)
Or don't sleep at night, grab the biggest shotgun you can get and shoot anything that moves. (your proposal)
Or you can build a 10m high wall around your wonders, with barb wire and state of the art security (former proposals)
For you own sake, do not look at what your neighbours have/get, yes you get a suzuki alto and your neighbour a Ferrari.
You can point fingers at the ferrari, but it's so much nicer to enjoy the suzuki then thinking about the ferrari you're missing.
You are making yourself nuts, you are making yourself go crazy, relax and enjoy life instead.