Most, but not all, of the superchargers I've visited are near dumpsters. In this case, the dumpster (barely visible in the photo) is behind the wood fence.Are there any Superchargers where there is a trash can? I'd be surprised. There is no maintenance at most locations. I guess there are people in the world who think trash cans magically empty themselves.
I was disgusted and angry when I took the photo & started this thread. However, as Gizmotoy and several others have pointed out, it looks like someone set the diaper aside for later disposal, and forgot about it. No excuse, but easy to do with a crying kid. Thinking about some of my own sleep deprived mistakes made when my kids were young restored my sense of humor. Thanks, all, for posting & helping restore my outlook on the situation.