The philosophy behind this model is one of freedom with responsibility. Joomla gives you the keys to the car for free, but the "Joomla subscription" represents the cost of gas, maintenance, and insurance. For the hobbyist, it is possible to run a small blog using free extensions and cheap hosting. But for the professional—the e-commerce store owner, the university, the corporate communications department—the aggregate of these subscriptions is a non-negotiable operating expense.
The Rise of Jooma: A Strategic Analysis of the Subscription Model in the Decentralized Economy jooma subscription