This sniper isn't a regular sniper, because it can carry shotgun shells, which gives it a radius larger for a kill.
This also would make it easier for people to snipe an enemy, and yet, the best snipers are the ones that required to take your time in aiming and make it harder for you to get an accurate shot, due to gravity, wind, etc.
Ok, let me get this straight. This is Blockland, not real life. Things can happen in game that wouldn't normally happen in real life. With this being said:
The sniper fires projectiles that may or may not be shotgun shells. It doesn't really matter as they will be treated like a regular sniper bullet. Upon reaching a certain radius, the projectile will spawn several more projectiles. These new projectiles will spread away from the initial shot.
This will not give the shooter a larger radius for a kill, but instead, make it slightly easier to achieve a kill that is at a farther range.
Also, "best" is a word subject to change and prejudice. You could think "best" means realistic, while I think "best" means easiest to use.
All I'm saying is that just because you don't like this add-on doesn't mean it shouldn't be made. Don't download it if you don't want it.