DS (19) has the world's most annoying habit.
He will make himself a hot drink, and for some reason he is incapable of keeping all of the drink inside the cup during the process. So tea/coffee/milk slops everywhere and usually sugar spilt too. He will then wander off and leave this mess.
Annoying. But he's not finished yet.
He will then return and, assuming I have not spotted the mess and exploded at him asked him to clean it up, he will now wish to use the same area to make a sandwich. But the worktop is dirty of course!
So - instead of getting the dishcloth/sponge and clearing it up, what does he do?
He gets the tea-towel and spreads it on top of his mess and uses it as his sandwich making surface!! 
Apparently my rage at this habit is misplaced and I am unreasonable... 