When we went on our first family trip, we bought the meal plan. When we figured up what it cost vs. what we would have spent on what all we ate had we paid oop, we realized that we grossly overspent by getting the meal plan. (This is a ymmv type thing, however.)
On our second trip, we did not get the meal plan. We still ate a character meal or an AYCTE/buffet meal each day (I say this to note that there is no sharing at these--you pay your adult or child price based on your age, and there's no deviating from that). When we ate at a QS location, we used that opportunity to split meals, or I would order a kid meal. At Pecos Bill's, we ordered two orders of the fajitas for the four of us. It was almost enough. My husband is a big eater, so he was still hungry. I think we got him something else later. We also bought snacks as we pleased, but it was not enough for the snack plan to have saved us money. We saved money by paying oop.
Also, our kids like popcorn. We bought a popcorn bucket, and refilled it as needed. We will do that again on the next trip.
We ate in our room or on our way to the bus stop most mornings, and that worked well for us. Granola bars, fruit, juice boxes, etc. Easy to carry and eat. Very inexpensive.
For the next trip, we will be in our travel trailer at the campground. We will average two meals a day at our campsite. (Epcot is the exception--all three meals there. Good food at Epcot.) When we camp, I tend to make a lot of meals in the crock pot, so we will do a some of that. Since it will be summer, we plan to have lunchables, chicken salad sandwiches, and other cold foods available for meals much of the time, however. We've found on our last few summer trips (to other locations) that we really just want cold food when it's hot.
I can make a nice meal for the four of us (and have leftovers) for what it would cost to feed ONE of us at a disney TS restaurant. Saving money making our own food at times makes me feel better about splurging on character meals.