Paid support, tools, there're plenty of companies which follow this business model. Extjs, Vaadin, Typesafe, etc.

I understand that they want to make a money, however, using their license is unacceptable risk, especially taking into account there're comparable alternatives. I'd rather use GWT/TypeScript/Scala.js, than proprietary framework which I won't be able to work with if they changed license to something unacceptable (for example, charge per server or whatever).