When SW is open late nights the All day dining can be a good deal depending on your dining style.
We go when gates open, usually 9am and have breakfast before doing anything else.
As the day goes on we often grab a drink to carry with us. Usually there is no need to go through the entire line just for a bottled drink.
Getting frequent drinks on the dining plan goes a long ways to saving quite a bit.
For lunch we often have BBQ at one of two restaurants along with desert or small salad.
After dark we'll use the plan to get hot chocolate or other drinks. Around closing time (9-11pm) we'll grab something for dinner.
If you're only going for a short day when SW closes early the plan probably isn't a good deal.
If anyone in your group has an annual pass then you can get a discount for the plan for the entire group.
If you do not get the plan then you might want to get one of their refillable drink mugs. They are around $10 but costs about $1.50 for refills throughout the day which can save quite a bit over their typical high priced drinks. If you have a SW mug from years prior then bring it as it can still be used for the refills.