Why hadn't she tried them yet?
She thought they were like Whoppers. (Anyone who has had the two knows they are wildly different candies).
But, why wouldn't she want a Whopper?
Because they are malt chocolate right? And malt sounds like mold, thus no Whoppers, thus no Milk Duds.
Perhaps we will be able to get her to actually try a Whopper one day. For those who don't believe me, I actually filmed this one.