Too expensive, and impractical. They're made of polycarbonate, which is more than sufficient to shield the eyes from most workplace hazards. Something striking with the force of a bullet, even if the lenses were made of bulletproof glass, would likely cause a broken nose and fractured eye sockets as the glasses were forced back into the face. Then there's the ricochet. The projectile could easily end up being deflected up into the top of the skull or down into the soft squishy face meat below.
Dang, you guys make me want to cook actual people and eat them. Although, it does sound like a good idea to kill the people I hate........
