
I've never heard of this before and didn't know it was a "thing" - though I'm not surprised to find it coming out of Hollywood.
Anyway, uhm so that sack they're eating is full of almost 9 months worth of fetus piss and shit... Call me "wasteful" if you want, but I would hope that as a higher species we can find better places to champion "recycling"...
you seem to be thinking of the amniotic sac, although it wouldn't have shit in it because the fetus does not eat and digest food yet.
I suppose not the "traditional" shit adults make, but they have "shit" made of like snot, bile, and other "gross" stuff.
Anyway, this ain't my department clearly; you're right though I do wonder if those two bits come out separate (so you can nomz just the placenta) or is the amniotic sac like a balloon and it pops and drains away? Funny, I've had two kids and had zero interest in researching afterbirth "waste" until now lol