At some restaurants "Specials" can  be lower  cost items... kind of like a sale on a variation of a menu item.  At other restaurants the "specials" are premium items at a higher price than regular menu because they are truly something unique that is not on the regular menu and may require special prep time. It is critical that the server mention prices

You are absolutely right and it is one of my pet peeves. One should not have to ask. As much as I respect John Fager we were not pleased at our Atlantic Hotel lunch visit a few weeks ago, after ordering a piece of cake to find it priced at $9. We were not told the price ahead of time and assumed it would be within reason considering the sandwiches were in the $8 area and drinks were $4. We called the next day to relay to John our displeasure. Andrea was there again for lunch yesterday with a friend and she said a separate sheet is now offered with the desserts and prices.