Pretty normal, the bow is standard, they are all like that.
The plastic shavings will just wear off or you can trim them with like an exacto knife and they won't come back.
I don't think there's any real reason for concern.
The plastic really doesn't do anything but hold the metal rails front and rear, the front doesn't appear to be much but it's modular and one piece, both sides all one piece of metal covered in tupperware.
I think your ok.
In Memory of Paul "Dietrich" Stines.
Dad: Say something nice to your cousin Shirley
Dietrich: For a fat girl you sure don't sweat much.
Cue sound of Head slap.
RIP Muggsy & TMan
"If you are a warrior legally authorized to carry a weapon and you step outside without that weapon, then you become a sheep, pretending that JOCKO will not come today."