I'm feeding raw, and I rarely see my cats drink now either. Dr. Pierson on her site www.catinfo.org
explains that cats are meant to get their water through food, which is why cats on dry food are chronically mildly dehydrated:http://www.catinfo.org/#Cats_Need_Plenty_of_Water_With_Their_Food
(bolding is mine)
"Cats are designed to obtain most of their water with their diet since their normal prey contains approximately 75 percent water. Dry foods only contain 10 percent water whereas canned foods contain approximately 78 percent water. Canned foods therefore more closely approximate the natural diet of the cat and are better suited to meet the catís water needs.
A cat consuming a predominantly dry-food diet does drink more water than a cat consuming a canned food diet, but in the end, when water from all sources is added together (whatís in their diet plus what they drink), the cat on dry food consumes approximately half the amount of water compared with a cat eating canned foods.
This is a crucial point when one considers how common kidney and bladder problems are in the cat. "