When you normally throw a snowball, you can usually see it as a circle from all sides.
What ended up happening was the snowball was rendered like an actual 3-D object that follows modern-day Newtonian physics. However, it was not rendered like a sphere, but rather as a flat circle, similarly to how items are rendered in Fancy mode, but not spinning. This happens in both Fast and Fancy modes.

EDIT: Same thing happens with eggs.

Examples are attached.