I think a lot of times they give out a smaller portion because we tend to WASTE so much food! We're so used to super sizing everything that we've really forgotten what a normal portion looks like. Then we get to our table..start eating and realize that we took too much after all. Or didn't like the dish...that we took DOUBLE portions of. We've got to learn to stop super-sizing every meal.
It's really amazing the amount of food we can put down at one sitting! Most likely a lot of the servers are shocked (at least at first) how much we cruise passengers can eat...But even more how much we WASTE.
Yes...it's true, we paid for the cruise and all the food we could eat...but really, it wouldn't hurt to start with smaller portions and just go back for seconds if we were still hungry...or wanted to nibble a bit more.