I drank from a cup of water while standing next to a water barrel figuring I could refill the cup once I drank from it.....nope the cup is gone along with the water....wtf? Is this a bug or am I actually eating the cup?
Been an issue since pre-EE. It's an oddity, because if you use it in crafting, you usually get (or should usually get) the cup back.
It is odd, because I cannot believe that it's that hard to fix - all that is necessary is to add an effect to the action that gives you a cup. Basically, Drink Whatever->Effect->Get Cup.