This would absolutely appeal to my family. We like the short trips, and we like sleeping in. Saving some money, having relaxed mornings, and then staying all the way to close without exhausting ourselves? Great.
Also, I bet it's that *staying until close* part that Disney is planning on this helping the bottom line. Dinner reservations, late night shopping--those don't happen if not-morning people are dragged out of bed first thing by enthusiastic family members. Yes, mid-day is jammed, but the ideal customer for these tickets don't care about that. They're path of least resistance folks, I bet, and they might not even show up until later in the afternoon (or do a lunch reservation, something like that). My 2 cents.