The legalities of this may be as you state, I'm not qualified to dispute them, nor would I want to.
Firstly, may I state that none of this is said to embarrass or point a finger at Cherie26 - we've all been there and there's nothing worse than a 3 year old screaming their lungs out because they're hungry.
The general point I was making was that as parents, there is an unquestionable responsibility to ensure that we never place our children in harms way, irrespective of what the vendor claims, i.e. the food isn't too hot, there aren't any small bones etc. etc.
In preparing a meal for a child (and remember, this is only a 3 year old), you'd check that it wasn't too hot, you'd cut it up into small pieces and you'd sit there to ensure that they wouldn't keep stuffing it in as toddlers are prone to do and end up choking. This is especially true when dining out. A small child doesn't have the ability to evaluate the situation - they're hungry and here's food! That's what Mum and Dad are there for, it's their responsibility.
I hope the situation is as you state and that the parent is able to win compensation for the pain and suffering of his/her 2 year old but it still doesn't escape the fact that they themselves had an obligation to ensure that what they were giving their toddler, irrespective of the claim of Dairy Queen, wasn't going to cause them harm.
You know, it's becoming increasingly evident that it's easier to blame someone else - especially when there's money involved for not taking responsibility for the most precious of gifts - our own children.