Yo so I'm a terrible lazy person and also mold makes me gag really easily and so does spoiled food, but if leftovers/whatever have been left in the fridge or on the counter (don't look at me, look at the open can of chicken broth my roommate has left out for like, over a week and probably going on two, man) long enough to be assuredly really disgusting, I have no shame: especially if I do not have a dishwasher I am more likely to toss the entire dish than wash it out. First, if you don't have a dishwasher it's likely you don't have a garbage disposal either, and that means your wasted moldly food scraps get real real real fast, and second, I'm convinced that i can't clean them well enough by hand without scalding temperatures to want to eat from that plate again.
So basically. In practice I totally agree. In theory I don't think I disagree either but I would argue slightly more for conservation just bc, you know, let's not waste.
But fuck no that tomato has mold on it the whole thing is going in the garrr-baahhhge.