I think mainly the thing is that the game, having a lot of random stuff, as you said it can be very different from game to game. So in general I think it's better to stay on the safer side, and better if players have money in excess than less.
Also my point was that you can have all the money/gems you want, but you still need to be able to play the game, use the right skills, etc. And if it's too easy, you can always increase the difficulty to make it more challenging
