Only powered snowballs fire in scattered bursts. With no glowstone, it's always a single arrow firing with normal accuracy. I'm cool with all that stuff, even as written… for powered arrow-balls. Normal arrow snowballs are too vital to mess with their accuracy (it's not like you can't just spam them anyway but sniper accuracy rewards skill. with spread you don't even have to aim, with perfect accuracy you do have to aim or you'll always miss)