1) Can we please stop using this hashtag. It's embarassing.
2) How can it possibly ever hope to be a sustainable model if Jolla don't take a cut? I'd be very worried if they didn't take a cut. It'd pretty much be signalling that they don't expect active Sailfish users or app development to grow at any time in the forseeable future, and therefore any revenue from it would be useless; a tacit admission of defeat. Most developers who might be willing to test the waters would see it as a very bad sign. Besides, what reason would Jolla ever have to help, facilitate or support Sailfish ports to Android phones if they're never going to make a cent from it?
3) Implementing Flattr support (or similar systems) is insanely easy. Like some of the other features on the roadmap, how did this not happen sooner?