Neighborly behavior
Sharing your apartment with a stranger is difficult, but also sharing your building with a number of strangers! We live in a society, and so we must be considerate of our neighbors, and vice versa, which sadly isn’t always the case. Dealing with noisy neighbors is tricky, since you don’t want to get into conflicts with the people you live with and have to see almost on a daily basis.
When their downstairs neighbors were being too loud time after time, partying all night and day, these people decided to shame them: they covered their windows with sticky notes saying they are loud and inconsiderate. The loud neighbors clearly didn’t take this complaint seriously, and copied their note, with an addition of a meme-sponge bob character, mocking them.