#1. Kids are encouraged to eat cake AND ice cream. Adults can eat it and not feel guilty about it because it's birthday cake and birthday cake calories don't count because "You never eat cake or ice cream".
#2. There are usually a few games that are played and there is nothing funnier than watching a kid play:
Pin the tail on the donkey
hitting a candy stuffed pinata until it busts
#3. After the cardboard structure is completely demolished (from either the kids or the mom beating it senseless) the kids experience the sugar induced state of euphoria from eating all the candy that they grabbed off the floor during the frenzy of trying to stuff as much of that sugary goodness into their little candy bags before the "candy police" stop them.
#4. There's always a couple of loners at the kids table
#5. And there is always a "big kid" that wants to play too!