I'm usually inclined to agree, but it's not as clear cut with Clash of Clans as a Zynga game for example. Clash of Clans follows a traditional RTS model, building things takes time. Now, they've given you the option to purchase gems to automatically finish buildings.

This clearly exploits people's need for instant gratification. However, that need for gratification is up to the user, not the game. The game itself is quite fun and easy without ever spending a dime. There is nothing "game breaking" that has to be purchased with real funds. It's one of the truer time = money models out there.