Yes it can, also they have an alternate restuarant where the buffet is located, it is by reservation my husband and I found it about the 3rd night out on the Millenium. It is a place where the waiters and staff are being trained for the regular dining rooms. The menu is a little limited compared to the dining room, but it was probably the best meals we shared. Every morning I called and made a reservation for us and we had the same table by a window for just the 2 of us. Had the same wait staff also and the food was great. The do recommend a gratuity of approximately $2.00 per day, we just waited until the last night we ate there and made sure that we tipped all who took care of us.
Also on Celebrity you can order anything on the dining room menu during the dining hours and have it delivered to your cabin.