Technically, "greasy pizza boxes" should be tossed into a yard waste cart. Realistically, is it fine if I put pizza box with just a tiny amount of grease stains into the regular cardboard recycling container? Or will that cause the entire global recycling process to come to a halt? How many grease stains are too many stains to make it eligible for cardboard recycling?

There have been times in the past when someone has removed pizza boxes I've placed in the yard waste cart; they moved them to the cardboard container, likely thinking I was stupid for using the yard waste cart in the first place.

At work people put all sorts of non-recycling items into the recycling container. I feel a bit silly being obsessed with grease stain percentages when I witness so many people obviously recycling incorrectly. That leads to another question about how well people in Seattle recycle when they do recycle, but for now I'll stick with just my pizza grease inquiry.