Its not like he was trying to hit a bullseye from 300 yards away. He was shooting into a crowd. I would imagine accuracy is secondary to rate of fire.
That guy is a dumb fuck.
Yes the more it spits out and the quicker it fires the less accurate it will be. I can see if controlled two shot bursts it could be accurate due to fire rate but when it spits out 20+ in succession you are just trying to hit the wall and not the apple on top of it