Did you just happen to see a photo pass photographer and ask them to take the candid shots? The ones I saw often had a bit of a line, so did you wait in line and then ask? And photopass photographers took zoom shots of various princesses during the shows for you? How do you ask for that?
I lucked out a lot of times with the candid shots. If I needed to, yes I waited in line. Kids get rather oblivious when it comes to eating ice cream waiting for a parade.
As for the princess shots, I just told them what kind of photo I was looking for. "Can you take a zoom shot of so and so?" MOST of the time, they were more than happy to help me out.
For the most part, if I saw a photographer and the timing was right, I went for it. Like I said, just outside the box thinking. No such thing as a wasted picture with MM, in my opinion.