Not only were 'in-app' purchases banned (unless they paid the entire 30% store portion of the sale to Apple), they had to remove links in books that took you to the website to purchase (which is what many of the apps had done, anyway).
We'd all love to see those features back, no matter which app we used.
I used to like Apple as a company. Once upon a time they flew pirate flags and took on stodgy IBM who Apple accused of practicing a monopoly. A la Animal Farm, Apple has become IBM or at least the perceived personal of IBM that Apple used to battle.