Two weeks ago I got off the Crown Princess from a cruise where I had Traditional Late Dining. Was assigned a table for 6 - 1st night there were 4 - 2 of whom didn't show up the next night but 2 others were assigned and came late. Next night I went to a great specialty restaurant - after having told my wait staff I wouldn't be there. Fourth night back to my original table for 6 and I was the ONLY one there - very uncomfortable - and not ONE of the people assigned had told the wait staff they wouldn't be there.
The next day ran into the assistant waiter and told him I would NOT sit there alone again - I'd go to Anytime. That night the headwaiter, waiter and assistant waiter were very helpful and moved me to another table. This one was one for ten people and only two people were there and that was the situation from the second night ... again NO ONE had told the wait staff they weren't showing. And one of the couples assigned the first night to this table for ten showed up the last night.
To me this is a VERY, VERY rude thing to do - not only to the passengers but to the wait staff.