[jruderman]

It often depends on your skill level, whether you take breaks from the game, and how much of a completionist you are. In some games these factors interact in complicated ways.

From a regulatory perspective, I'm afraid the best we can do is:

* Ban tying game mechanics to time outside the game, whether it's "wait 8 hours unless you pay" or "this reward is only available for 4 hours" or an insidious combination of the two.

* Increase transparency, e.g. by asking app stores to show graphs of (time played) vs (money spent).