The Aimpoint Comp series of sights provide zero magnification but do add a red dot reticle to assist in aiming the weapon. If you look at the front of the shotgun you can see it has a bead sight and at the rear of the shotgun you will see it has no sight at all (the Aimpoint is mounted on an aftermarket rail). Individual shotguns may or may not have quirks where they shoot on an angle away from the point of aim. While it is a shotgun and you can use shot shell, even at ranges of 10 yards and more it is beneficial to have sights you can adjust to properly zero it so it shoots where you are aiming. If you were to ever switch to slug or other solid ammunition this would be an even greater issue as you would no longer be firing multiple smaller pellets but one large projectile. The Aimpoint allows you to adjust for proper accuracy on top of the already mentioned reticle.
