There are actually two separate and mostly unrelated issues in play here ... insulation (energy savings) and plastic disposition. Trying to "kill two birds with one stone" in this case may end up solving neither problem and might actually make things worse. Thermal transfer is a very well understood science and insulation technology is available and inexpensive. If you want to save energy, save the planet and stop putting carbon in the air, then place appropriate amounts of insulation in your dwelling. Rock wool is a terrific alternative to pink insulation ... easy to come by and not very expensive. Now, what to do with all that plastic? Well, first we should figure out how to stop needing and/or using it ... cloth or paper sacks is a nice step in that direction. Second, we need to find a efficient way to collect it and then lastly, of course, remanufacture it into something useful ... or even decompose it and return it to the Earth safely. Trying to solve both problems, one user at a time, is not going to help much ... if at all?