Keep in mind that none of these baggies are made for the purpose of holding boiling water to cook food. Even the freezer bags will impart some of the bag into your food. Sure it’s minute amounts, but still not worth it, IMO.
Why do people think cleaning a pot is such a big deal?
If you want to avoid a hard to clean pot, just put enough water in for the meal. Food sticks when it gets too thick.
I boil my water, then add what I’m cooking, stir it, put the lid back on, then turn off the heat. Let it sit 10 minutes while I set up camp, get more water, etc. After I eat, if there is any food residue in the pot, I add some water, swish it around, and drink it. This method works great with my cookpot, which is not non-stick.
RenMan