answer:I didn’t know that. Really? Who is going to bother to cut out the greasy portion of the pizza box. I recycle pizza boxes and paper plates by burning them in my wood burning stove and converting them into heat. 15 pounds of cardboard has the same energy content as one gallon of heating oil. By burning it directly in my high efficiency (73%) wood burner I am effectively converting it into heating oil. In the summer, old pizza boxes make the best firestarters for camp fires. By the way, in my area, a used pizza box in the recycling container is sure attractant for raccoons and other critters. You will wake up to a mess all over your front lawn.