Lest you think I'm some sort of madman, I suspect the hygiene problem is quite mild. But speaking as someone who has washed dishes for a living, people can be q

Lest you think I'm some sort of madman, I suspect the hygiene problem is quite mild. But speaking as someone who has washed dishes for a living, people can be quite disgusting with their food and that does get to you. Having an attitude where you say "why don't they just do this" is typically not helpful. People are smart, they probably have already considered your solutions. If someone doesn't do something the way you think it should be done it doesn't make them stupid. Trying to figure out what you are missing when a solution seems obvious is a helpful way to see the world.