I think the waste of food is far more egregious than the clean up. and him plastic wrapping anything first doesnt make it any better. Just more wasteful.
It is near impossible for a consumer in the US to waste food.
This is because the massive amount of waste that's produced by grocery stores makes any conversation of consumer waste a moot point.
In this instance, for example, if he didn't use that Nutella, odds are it would wind up in the dumpster a few weeks later, still completely sealed and untouched by anyone.