I am pretty sure they do. In april 07 for our last trip they had them at Riverside.
They also had them at both water parks, PoP and one spot in Epcot.
Our son is also very hard to feed and he loves those..
For our 2008 trip we are ordering a box of them from one of the online grocers that people here suggest (want to say green grocer, sorry but it is my favorites at home). That way we are set at all times.