I think the +1 DM for using a Laser Sight is a fair bonus in terms of game mechanics. As others pointed out, there's myriad variables and factors involved in making an accurate shot. And laser and red-dot sights are mostly intended for CQB. Now, I will say, based on my own experience in Afghanistan, hitting a moving target even at 25m using a weapon that's kitted out with the latest bells and whistles is a bit tricky in combat.