For the same reason the average American citizen may need a gun - defense. Body armor never hurt anyone - it's strictly for defensive purposes.
I bet those people defending their homes and businesses during the Fergeson or Baltimore riots wish they had body armor. Most likely you (or most folks) will never need body armor; in the same vein, most folks will never need a gun.
If body armor were to be outlawed, there is no way to stop people from making their own. You'd have to outlaw the materials and even steel plates. Give me a sewing machine and a gas welder and I could probably figure out how to make body armor.
I bet those people defending their homes and businesses during the Fergeson or Baltimore riots wish they had body armor. Most likely you (or most folks) will never need body armor; in the same vein, most folks will never need a gun.
If body armor were to be outlawed, there is no way to stop people from making their own. You'd have to outlaw the materials and even steel plates. Give me a sewing machine and a gas welder and I could probably figure out how to make body armor.