There's also the people who leave dirty dishes in the sink. Forever.
My last office, this was a huge problem. It was a small, family-owned company. The owner had made it clear, many times, that she really didn't like finding dirty dishes in the sink every time she entered the kitchen. But there were several people on staff who would eat lunch, leave their dishes in the sink, and "take a break" later in the day to come back and wash them. Just a way to get out of doing 10 minutes of work. Or they forgot and didn't come back until the next day.
When we were moving to a new office building, we had the opportunity to put a dishwasher in the break room. But the owner decided that we "didn't deserve one," because of all the people who didn't wash their dishes promptly. It was such a little thing--just wash what you have dirtied.