By the fact that more than half of a FPS community is always filled with 360 kweekskoap tryhards. (ok maybe not, but snipers nonetheless)
Seriously though you have the choice between a SMG that might work like a weak assault rifle, a shotgun that owns at close range, OR a sniper that can 1sk pretty much anyone from all range. What people will choose is kinda obvious
I don't know much about other special slot weapons, wasn't there a pistol other than handcannons?. Maybe swords?