I think this is a fundamental truth that is rarely acknowledged by the creators of "free" services. Delivering value to your users and increasing profit for the company are almost always in direct conflict. Large groups of users are drawn in by a free product which will ultimately be unsustainable. The companies which succeed after this initial period are the ones who are willing to degrade their original product, and manage to do so gradually enough that it doesn't draw too much backlash from their existing users.