What is the point of the Anti-Gadoid gun in Dying Light?

I found the Anti-Gadoid Gun but can't figure out what to do with it:

I have seen on the web (link above):

The Anti-Gadoid Gun is a troll by the developers

Is that right? It doesn't do anything? You can't use it on a side quest or something?

Solution 1:

The gun is a troll put in the game by the developers, it does nothing, sell it.

Solution 2:

The gun actually isn't useless or a troll.

The gun, when fired, sets out a noise that attracts infected to you. Whether it be a walkee, runner, or a viral. Therefore, you can use it as if it is a firecracker, firing it in on spot to draw the zombies attention, then running around.
It does not use any ammo of any kind. It says it uses pistol ammo but it will never load nor shoot any. The bullet counter will always remain at 0.
It can also be given to Dawud (I think that was his name) for the Gunslinger quest.
It is also used in one blueprint but I have yet to find the blueprint or the name of it.

Solution 3:

When fired, it creates loud noises which alert special infected to your location. Firing DOES NOT use pistol ammo.