I feel your pain. DH loves the dining plan and fights with me every trip. We finally decided that we would alternate. Every time we use the dining plan I go through the pain of showing him each and every receipt and show him how we LOST money on the dining plan, but he doesn't care. Makes no sense to me. he swears without the dining plan I wouldn't feed him. Yeah ok. I feed him at home.
Anyway....I have stayed at the S/D and I LOVE it! The area is great. Being able to boat or walk to two parks is unbeatable! The Grotto pool is really nice. It's like being at a deluxe for moderate prices (DH is a gov't employee, so I get that discounted rate too).
You won't be able to use your room key to charge back to the S/D from the disney parks. However, you could take the exact amount that the dining plan would cost you if you were staying at a disney owned hotel and put it on a disney gift card. Then you could use that gift card for all of your meals. Besides some of the smaller stands, I don't think you would have a problem using it anywhere. He might feel like he is on the dining plan if he is not putting a penny out of his pocket. Just think apps and tips could also be debited from the Disney gift card.
As far as saving money on food. We always get a Garden Grocer delivery (we go shop is another option). I spend about $100 and get cases of water, breakfast foods, snacks. Except for breakfast maybe once or twice during our (usual 10 day trips) we eat in the room. We put water in the refrig every night and bring a bottle to the parks. We also bring those crystal light single packets so that you can have iced tea, lemonade etc.
Another way I cut down on food is I belong to my points. I do the surveys. Click the ads. and go through their site when I order online. I specifically use the points for Landry's gift cards (Rainforest and TREX). I'm not sure when you are going, but after a year of doing it...I usually have enough points for $100 in gift cards.
Regarding the disney gift card, if you have the target credit card then you can get a 5% discount on purchase. That adds up as well.
I would check out the budget board for loads of ideas.