We don't do the specialty restaurants, but I've always been under the impression that the surcharge included the tip. Even if the food and service is superior to the dining room, $35 p.p. is a fair hunk of change.
We consider ourselves to be generous restaurant tippers-never less than 20% unless it's really bad service and/or food but I think the tipping thing can get way out of hand. Another reason why we choose to stick to the dining room.