@TokaiTele
Microtransactions will cost some people money that should not have had access to spending those money as they are too young or irresponsible. Also if microtransactions are used in a pay-to-win manner it can break a game. These are two aspects that may give games a bad reputation and create problems in some peoples life - Still there is not only bad sides, done right it can be a good thing for a game, bear with me for a moment:
People can get addicted to almost everything that is fun, alcohol, sugar, fast food, driving too fast, still the world would be less off without fast cars, good wine, late night fast food amongst other things that needs to be enjoyed responsibly. We can't ban everything that can be misused just to keep the crazies in check.
I would not compare fast cars with micro transactions as sources of joy, but they are comparable in the way they both can lead to good consequences. Fast cars will give you an adrenaline rush, and well, microtransactions done right can give the devs more leeway to make a more fun game by having more money to spend. No doubt about it.
Microtransactions only used on cosmetics which gives no upper hand is an example that will not be pay-to-win.
The other part about youngsters spending dads credit card also have several solutions. First and foremost you can have a strong parental filter. Have it so you both need a credit card and a phone code or similar to being able to perform a purchase, secondly you could have a maximum amount of transactions possible within a certain timeframe, thirdly you could add a safety filter that would disable the credit card info every third month or so, making the occasional smart rugrat loose access to the card details and phone he stole anyway after a while - though in such a case either his/her parents are too stupid to raise a child or the kid is too smart and will end up a professor or drug addict no matter what restrictions he/she gets=)
Bonus: Adding this heavy filter can be marketed as being a responsible developer and before you know it every mom will be obsessed with having a Sandstorm copy for her toddler so "it" can make America great again in a user friendly way.