I think it is important to remember that environmentalism is always loaded with trade-offs and there are many aspects to it as well. It brings to mind vicious yet silly lawsuits between plastic and wooden pallet makers over which was more environmentally friendly given variables like weight, fuel consumption, ecosystem impact, and biodegradability.

If you really want to be a smartass you can say with one hundred percent truth that styrofoam and plastic are better for carbon long-term compared to paper and cardboard which break down over time and release it into the atmosphere. (Ignoring the relative accounting of the manufacturing processes themselves for now.)