What ever happened to just paying $40 for a game and getting to use it forever? (This killed Candy Crush for me. I love the gameplay dynamic and the graphics, but the constant upselling just makes me want me smash my phone into a fine paste and then feed the paste to the game's developers.)
If they charge $40, nobody is going to play the game.
Not a supporter of the app, but it's pretty obvious the pay for bullet business model is the correct decision. It's hardly much at all considering the potential entertainment value for those who play it. Consider how much you would have to pay for paintball.
It's strange, it seems like on every single topic, nobody on HN wants anybody else to make any money at all.
Depends on your definition of "serious".