When I say all this I am in no way being disrespectful, and its pretty obvious that its a ploy to get them to see it from my view. But I guess when your bored and want to pick things apart it may seem like being disrespectful...Trust me on this, I am in no way when this occurs, just a little role reversal to help see things different.
I simply take it to the same level they took it, but with there beloved pets. They usually laugh, and say "yeah I understand, but there still gross..." I then walk away without being angry and they realize they were out of line. Simple, not complicated...