You can clearly see the odds are against you with the 2p waterfalls and such like. The side exits ensure the odds are with the house - you can point them out and show it's a rigged game. Opportunity to dive off into risk/reward and the unbalance of economics where some get disproportionate reward for the same inputs, perhaps? Or show how the house always wins. :)

Those aren't going to break the bank though, or start a habit, so a harmless way to let the kids get rid of parent's pocket of excess coppers.