Well, a lot would depend on the specific plan you're on, but I'm happy to share my own discoveries!
The Brown Derby in Disney/MGM has an unbelievable Cobb salad, which can have chicken or shrimp added to it for extra protein. The Columbia Harbor House has a memorable salad with greens, feta, chicken, pecans, and pineapple that's worth an extra trip to the MK, as if you ever needed any reason for a trip to the MK. I didn't eat the pineapple, as I was just out of Phase 1 of Atkins at the time. The breakfast buffet at the Crystal Palace in the MK has lots of faboo choices, like omelets, ham, and sliced tomatoes, and all that with a big hug from Pooh! Caesar salads (hold the croutons for low-carbers) can be found in a number of places, such as Cosmic Ray's in Tomorrowland. I had an amazing mixed greens salad in that big food court in The Land at Epcot, but I think I've read that they're changing that whole area.
More upscale, I had a stunning Planked Salmon at Artist's Point at the WL, and there are always fabulous choices at the California Grill.
To my way of thinking, the most important thing about treats is to make the decision BEFORE THE TRIP about what you'll do. It's fine to say 'No treats, I just don't eat that way anymore' or 'One treat per day' or 'One treat per trip,' as long as you've worked it out for yourself before temptation is staring you smack in the jaws.
Boy, now I'm hungry.