When moving at supersonic velocities, barely nicking something is still enough to transfer enough energy into the ear to, at minimum, leave visible scarring, more likely, require reconstructive surgery.

No. They either ricochet off the drywall to make a cool peeeinggg sound effect, or splatter you like a bug in Starship Troopers. Even a .22 short.

But every gun is a M2 or Barrett.