When we were at WDW in late August, they enforced the meal components - meaning no extra drink in place of dessert. I'm not sure that there would even be a way to ring this up if they would make the substitution for you. The deserts were limited, most places we ate at only had 2 or 3 choices. I remember fruit being a side in place of fries (grapes or carrots?), but don't remember it being a desert choice. Can you tell what a healthy eater I am while on vacation??