Also, I think there's something to be said for scale and context when it comes to regulation of this sort of marketing. Another poster here put it quite succinctly saying, I'm paraphrasing, "You don't expect them selling guns at the candy store."

So the App Store is something which a large subset of the global population has shoved in it's face, just for having a phone; which society expects of them. It's not people seeking out a "gambling-type" experience.

There's a greater onus of care to be a responsible player. I guess then they'd sell less of the self-help and counseling apps on the store too though.