Re: What I learned from our local preschool for disabled kids....
Is this a publicly funded program and are the students low income? I remember several years ago I worked in an after school program in a city middle school and the snacks provided to the kids were things like sugary cereal and snack cakes. Sometimes those are the only kinds of things they can get if they are required to go through certain food service vendors and/or are on a really tight budget. Also, in some situations the mentality is that the kids are at least getting fed, whereas they may not be getting much at home in low income situations.
Also, as others have said, I think the candy as rewards is a pretty normal thing in special education and I wouldn't be concerned about that unless there was some indication that the parents were unaware of it.
It does seem a little weird that they specifically mentioned the healthy food, though.
*Insert list of crunchy mom stuff here*
ISO Zutano and a Ponyo DVD, IHA 2t Antsy Pants and size 1 Piddle Poddle trainers