Given how paranoid I am, I think it is code for someone outside. Like, "dont rob this guy, he paid." So i take the water. But then I get paranoid the cops know the code and are also watching the place, and will think it means I am a perp. So I hide the water, but am ready to bust it out if I get approached by anyone doing a "water check." Once i get to the car I drink it and throw thr bottle away immediately, just in case.