Are you aware of the fact that most molded containers, just like the ones you use (the 'cardboard' where you put the food) can be dangerous? As greases, especially hot, destroys common cardboard those containers usually contain PFAS, a chemical which is the reason why those containers are so difficult to soak up. This is a widely used product, for example on clothes, to waterproof things. However using it on material coming in contact with food, especially hot or greasy, may be dangerous because the product leaches into the food. Previously used molecules in this family are named pfos and pfoa, are now already classified as dangerous (for human health) and global pollutants, and not produced anymore in most countries. There is now a major concern about PFAS found in drinking water in a growing number of nations, including the US, some class actions may follow, and it may become one of the most prominent food scandal.

To be on the safe side may imply to really check that the containers do not contain such molecules.