Melissa's situation is different from yours. You save more with
free dining because you have kids. Kids essentially stay free in your room (no difference in room rate for the kids) so 40% for her, with no kids, and you, with kids, is the same. But Free Dining applies to your kids too so its more a savings because it would cost you more than Melissa to pay for the dining plan (the price of the kids' DDP). Also, Melissa will be on her honeymoon according to her siggie so we don't know what type of room she has booked, likely more than a standard.
Make sense?