Oh my, such health conscious kidnappers.... bottled water at room (car) temperature wouldn't be good enough for them... they bring along fresh fruit for their little trip?
Once they are out of Boulder they can stop at any 7-11 & grab a few drinks & snacks.... throw the kid in the trunk of the car & you're just a regular hungry customer.
Not to mention..... HOW dry would their house have been that these kidnappers would worry about hydrating the child even BEFORE they started on their trip? Is that why they didn't leave the house as soon as they grabbed her.... they were waiting to see whether she had enough liquids in her body & if not.... they would feed her MORE pineapple until they were satisfied she wouldn't be thirsty in the car?