Sponge hierarchy, I have that too, well I mean, I have come into a household that has that. And never leave the dish sponge inside the sink either!
It goes dish ->kitchen (counters) -> bathroom 1 -> bathroom 2.
Bathroom one is the sink and bathroom two should be the toilet/bathtub but since I'm the only one to ever do them I just use the same sponge.
It's mostly a dust/ some kind of dark particles problem anyway.
And for those that didn't knew and are not bothered by it, you can put you sponge in the dishwasher or nuke it in the microwave, it should kill everything and promote back the sponge.
As for dishwashers, if I'm the one to put the cutlery inside, it will be handles up. Anyone disagree they can fill it themself, my reasoning being that how many here remember to wash their hands before putting the clean dishes away? I would guess not everyone, so that when you get the fork or the knife that are handles down, you are grasping them by the places that touch food, with your not-clean hands. And for knives there is less risk of cutting yourself.
Sadly I have yet to find someone that understands me.