At DLR, I also use my pass to get a discount & always get water instead of other beverages.
I will also say that the 2 credit meal plan places are usually the best and worth it.
As for eating less, you are on vacation! I will admit that I try to get the best food for my money.
My family has a rule: no burgers, hot dogs, chicken fingers, or pizza at Disney World (except Via Napoli)
You forget a simple way of saving money. Bring the packable sandwiches, chips, snacks, and soda. I will bring pre-popped popcorn in a baggie. I done this at theater shows.
Remember why you go to a certain park. At Disneyland, I think of Churros. At DCA, I think of corn dogs. You can bring them to the park. Pull them out when you have a craving.
We eat before arriving to the park, & usually on do 1 main meal at the park (cause we will eat after leaving the park as well)