insulbrite and a layer of warm and natural

Please forgive my asking, I'm really not trying to be 'contrary', but can someone tell me why you use Insul-Bright?

-it is clearly not thick enough to prevent heat transfer all by itself (even the manufacturer says to use it with a layer of cotton batting) so the heat reflecting properties aren't all that great;
-it's made entirely of polyester, a fiber that melts and sticks to the skin if it burns, and there have been multiple warnings all over the internet about using polyester batting in potholders;
-the care instructions call for cold water washing and no bleach, perhaps not the best way to wash things that can easily come in contact with food;
-it has no fire resistant properties whatsoever, and does not claim any, so it is no safer than any other filling;
-and it costs half again as much (149%) as plain cotton batting.

What am I missing? What makes this THE filling for quilted potholders?

I'm going to have to ask a dumb question. Is insulbrite some sort of silver metallic fabric ? Maybe like thinsulate that is put in gloves and stuff ? And where do you get it ? Thanks