Not everyone orders the stateroom decorations so of course you will still get a cake in the dining room....it helps to remind the wait staff. You also must have it noted on your reservation that you would like a have a special occasion celebrated in the dining room. If it is not noted on your ressie, your servers have no way of knowing you are celebrating something.
This past week we were supposed to have a cake for anniversary on Monday night....because we did not board until late Monday and our dinner was messed up we never got the cake...I did not mind at all. I am sure if I reminded my servers they would have brought me one but I decided on the other desserts instead!!!
MJ