This is a brilliant cost-saving idea. Let's say you're throwing a party and want one of those beautiful designer cakes but don't want to spend the money, what do you do? Buy a fake cake instead.
The fake cakes are covered in fondant, which is what cake designers use, but underneath it, pure Styrofoam. And the idea is this... At your party, everyone gets to marvel at your beautiful cake, but then when it's time to eat it, it gets taken to the kitchen to be "cut" and instead you serve a much less expensive sheet cake in the same colors in it's place.
You can even make one of the tiers real cake so if it's a wedding, you can do the cake cutting ceremony and no one will know the difference. And the cost savings... One of these cakes costs about $250. A real designer cake costs about $2,500.
Like I said, brilliant.