Alas...the dining plans to my knowledge have never been available with the campsites due to the 10 person per site allowance.
I will say IMHO since the conception of the dining plan;
(a) the price for meals has noticably increased for non-dining plan guests
(b) the quality of the meals has sharply declined
(c) reservations to restaurants are very difficult to get
(d) for those using the dining plan your trip centers around eating and not enjoying yourself.
Personally, I wish they would eliminate the dining plans and go back to the way things were. We used to enjoy going to a WDW restaurant to enjoy a nice meal that was somewhat reasonably priced and being able to go on the spur of the moment. WDW restaurants used to be noted for being a notch above the outside restaurants because meals were cooked to order, but not any more. It's mostly mass-produced, pre-prepared & then nuked to heat crap now.
AND...for those who think they are getting something "free" with the dining plan, guess again. Disney does not do "free". You are paying for your meals in your vacation package. It's just not itemized as such. The only advantage to the vacation packages is that you know up front how much the entire trip will cost - inclusive of meals and snacks. It's cruise line pricing mentality.
I suppose though if you are staying at one of the value hotels..the dining deal might be a better value then say..if you're staying at a Deluxe resort. Certainly paying full rack rate for the WL and getting free dining..isn't any kind of deal. I'd rather get a good room only discount, and pay for my food.
We did the dining plan for the first time three years ago. In all our years, of visiting we never used one. It was NOT free. We did however have a good rate on a room at the WL. One of those PIN offers..and it was some $160.00 a night Courtyard view...then we added, and paid for the dining plan. Which I have to tell you was a lot of fun. For less than $40.00 a day..my kids ate really well. With teenagers this was a good deal. We all enjoyed ordering appetizers (which we normally don't do..we usually share things) and we tried places that maybe we wouldn't have normally..because we would have wanted to be more careful with where we spent our dining $"s. My husband LOVED that he wasn't taking his wallet out of his pocket every other minute handing the kids money. We also didn't have to all eat together. If the kids were at the resort..and we were out at park, we could eat separately. It was a pleasure not having to worry about leaving money for the kids or how much they'd need for meals if we weren't together. It isn't unusual for us to do separate things and then meet up for dinner in one of the parks or back at the hotel. Our kids are older. We almost always have a least one sit down meal a day as a family..so there ya go, it worked.
All that being said..I don't think I'd do it again. Because the very thing that we enjoyed most was the
convenience of the plan. That in itself was worth something to us. They have taken that away by not having the gratuity included and by removing the appetizers. That was part of the fun..and we know we're going to order a least a couple of appetizers to taste or share..so again, that takes away from the convenience of the plan. As far as I'm concerned they should have kept it the same, and raised the price rather than start to chip away at what was good about it.
You're also right..the restaurants also don't offer the same value as they did before either.
Last two visits I found using the Tables in Wonderland card a better value..with the 20 percent discount. Worked for us.
As far as not offering to the campground guests because you can have up to 10 people on a site. Given the increase in rates for the sites..of paying near or over $100.00...Disney might give some thought to offering it on a limited basis..say only offering it for up to a family of 4 on the site. Same as the resorts. The values only accomodate four people in a room. The campground could do the same. Offer it to four people in the party on a particular site.