I remember one of these coolers from the last job I worked! Let's just say that before they called me "Water Cooler Chris" I had a more sugary, carbonated nick name. Also, there was a lot more of me to go around.
There's a Greg in our office, and this flowchart would work perfectly for him. Except it would be placed in front of the coffee, and instead of asking if he has permission, it would ask "Did you make the coffee? Have you ever made coffee? No? Then go away."