You realize the mobile gaming market is mostly micro transactions and it has nothing to do with Google? The same happened to the PC gaming over the last ten years. You can blame customers for their human nature of feeling good for beating their in-game enemies with money to compensate for their psychological deficiencies.
I agree the dynamic you are describing is at play.
I also agree individual's are responsible for the actions.
but don't do the libertarian faceplant of then concluding that this is a purely individual problem that can't be understood in a systems thinking way where incentives to actors in a system can either be designed to excaberate tendencies and weaknesses or mitigate them