Why did I need the water? Simple: To go back upstairs into that original room and splash that water into the face of Tony Randall!
Well, I say Tony Randall, but I know that really it was Felix Unger. I know this because the reason I was getting the water to throw in his face was to prove a "fan theory" that Felix was in our universe.
Don't ask me how Oscar Madison fit into this. Don't ask me anything else, really. In fact, I woke up before i could get back upstairs, which leaves me disappointed yet kinda glad I didn't ambush Felix with a couple palms full of tepid hotel fountain water (Do they even have standalone water fountains in hotel hallways anymore)?
Don't assume anything except that it was one weird dream!