In the US, at least, you have a significant portion of the population with a puritanical bent. To top it off, they’re extremely vocal, political, and organized.

Right or wrong, advertisers are terrified of angering these people.

+1 for RB

I’m completely addicted (I’m in season 90 or so); it’s my go-to when I’ve just got a few minutes for a game. I think it’s one of the best games on mobile.