Foiled!

Every day my hotel gives me four free bottles of water, which is essential in a city where if you run the tap water over a white washcloth, the washcloth will turn brown. Sometimes four isn't enough though -- I get really thirsty -- and on the other hand, when I don't use all four, they only replace the ones I used. So a few days ago I began stockpiling. I'd hide any unused bottles each day in my refrigerator, and each day they'd bring me four new ones. So as of this morning, my secret stockpile was up to four. Apparently they're on to me though, because I hid another bottle this morning, but today they only brought me three!