Lukem,
I didn't mean for that 'back before we knew better' to sound disrespectful or rude. I probably should have phrased it differently. My apologies if it comes across wrong.
Aside from the fact that they are not 'food grade plastics', it is my understanding that most/many garbage bags are treated with 'anti-odour' agents, whether scented or unscented, and are not recommended for contact with foods. This is all I can remember from when I researched this subject looking for answers and trying to decide if the 'real' game bags and baggies were worth the money. I believe the USDA site had some good information. I'll see if I can find you a link.
FWIW & IMO, cooling the game is super important no matter what it's being packed in. But, you're already well aware of that...