They have a great idea on making money of users. Instead of charging a larger amount to let them play the game, they charge a numerous smaller amounts for different objects in the game. First, people are more willing to part with, let's say, 25 cents for that one cool fish than with 25 dollars for a game. Second, once you get them pulled into the experience, they will be even more willing to spend money. Surprisingly, I don't see that kind of pricing used much in other areas.