Well, that's the case 99% of the time. Only players with issues actually speak up. :) Regarding FB, all I can say is that there are aspects of the game that are outside of our control.
If you have lost your progress on FB you will likely not be able to get your progress back. However, you can work with customer care to retrieve currency.
Some of the games do specifically provide that option if you purchase something. For the ones that don't explicitly say that, I do believe the ads are tapered down with IAPs. Not completely sure on the cadence though.
You're correct on both of those statements. :) Also, the next update includes some of the most highly anticipated/requested additions to the game. But that's all I will say.