Few years ago DXB-BEY, one of the few times in Y with EK, noticed a 5-7 yr old child collect the amenity packs that have the stickers, open them up, then put the stickers on the wall. Her parents were either busy talking or uninterested that by the time we're about to pushback there was like 30 stickers in a U on the wall. The sight of those stickers made the cabin feel very cheap (how can subtle things affect that!).

But yeah, nothing beats a passenger eating a towel. Though gotta ask, since when does EK provide a hot towel in a plastic wrap? They usually hand them out using tongs in all classes. The towels come in trays that the crew open and throw hot water on them, sometimes with perfume.