I agree ... this has been a sensible, logical debate, ... which has proposed some good pro's and con's.
I have seen copies of the Plastic British para badge, and AAC badge.
The only clear reasoning for these specific copies comes down to the open market price of the original items.
The original of these both have roughly a present market price of around the £100 GBP mark.
.. And from what I suspect, the basic production of a set of molds has, through computer and laser cutting technology, become fairly straight forward and cost effective.
Also, bare in mind that it is plastic being cast, which involves lot lower temperatures and skill.
I will try to find some images of these modern copies to gauge some differences.