As most of us know, you never want to long-term store chips in them..I use them only to mail a chip as an extra layer of protection.

My question is there are non-PVC safe plastic sheets that don't hurt chips but why don't they use the same material for flips?

I guess that's like if the black box is the only thing that survives an air crash, why not make the entire airplane out of the same material as the black box?