We get the DDP almost every visit and pay for it out of pocket. We are DVC, so we don't get the seasonal upcharge (as a teacher, we almost always travel in peak seasons). We have crunched numbers MANY times (esp. comparing to TiW) and the DDP always brings us out ahead. Would we rather an appetizer than desert, many times yes. Would we always buy a desert, no. We figure all of that into our calculations. It all depends on how you eat if it is worth it.
A basic day for us (two adults, 1 7yr old): get up and make coffee in the room. Put it in mugs and throw a bottle of H2O in the pack. Once in the park, use 2 snacks for pastries ($6-7). Some time in the late morning/early afternoon, go to a character meal ($70-100). Grab an ice cream somewhere midday ($3). Then in the evening, we get a counter service dinner ($35-45). So we get between $114-155 worth of food daily. The plan for us costs $105 per night. So, we might save a little, we might save a lot. TiW card would save us $15-20. So, for our average 5 night stay, we save about $120 with DDP, and would save about $25 with TiW (subtracting cost of card). Two trips a year and that's $240 with DDP, $100 with TiW. If we just ate what we wanted (less deserts, more appetizers) our average daily cash cost is a little more. So, we forego the appetizers. If we REALLY want one, we buy it. Many times, our counter service deserts go in the backpack and become the fireworks snack!
I've posted this before in other discussions. Your results may vary. The DDP fits our dining habits pretty well, so we get it. Was it a better deal before, certainly. But, for us, it is still a good deal.