Now I am all for not being able to obfuscate the actual costs of IAP. This method is used a lot by supposedly free to play MMOs. You don't buy items/upgrades/boosts with real money, you buy another currency to buy these IAPs. Worst, most purchase quantities are set to purposefully keep you from getting the exact amount you need.
Apps are merely doing what has been happening in full on computer games for years. The difference is that many purchases are made by children because insufficient parent oversight. So instead of putting the blame where it belongs we go after those who sell it?