My impression is that Xamarin is designed to suck dollars out of corporate enterprise users who need to do something with mobile devices and can pay big bucks for Xamarin because it allows their C# devs to make a mobile app in short order. It saves them in the long run.
They have a community edition but sell a corporate version with Xamarin Studio & SDK (not in community edition) for an unspecified price. It used to be $1,000 per developer.
