I also leave Coby in a crate while I'm at work, and also come home for lunch. Coby has water in the mornings and then potties before crating. There isn't any water in the crate. When I get home for lunch, he does not seem overly thirsty when I first let him out. I think it might depend on the age of the pup. Younger dogs might need more frequent hydration.
My older Shih Tzu has the run of the house and I envision that he drinks water in front of Coby's kennel and makes extra slurping sounds and tells him how wonderfully refreshing the water is.
