Not mobile as far as I know, but Prodigy (prodigygame.com) is allowed/encouraged at my kid's school and has a lot of these traits. There are treasure chests at the end of a battle, gems or coins collected, and a constant reminder that subscribers get more rewards. Many of his classmates subscribe.
Ugh, yes. My kids play this one at school and when I read about the game mechanics I was super disappointed. Luckily they stopped begging me to subscribe eventually since I wouldn't budge.
The problem here is it's a lose-lose situation for the consumer. Either the incumbents push regulation that benefits them at the expense of new business and consumers, or regulations are removed and businesses (new and incumbent alike) get free reign to apply any consumer hostile money making scheme their hearts desire.
The latter isn't the dystopia you seem to think it is.
We have plenty of existing rules that are fine for enforcing access to markets.
There are tons of people who want to make great products and tons of people who want to buy them and tons of people who want to make them discoverable.
The issue is that large lawbreaking organizations are actively inhibiting that.
Consumers are good at avoiding consumer hostile vendors when they are actually given choices and opportunities to do so.
My advice to law makers is to regulate these games into the ground. Your statements enforce my world view. My kid will not play these games.