Pinterest, Instagram, Groupon, Zynga, and "in some cases billions of revenue"? Unless I'm looking in the wrong places, that is a factual error.
While getting hundreds of millions of users is great, it's not quite the same as getting to profitability. If you're using Zynga and Groupon as success stories, your business model might very well consist of, "looking for the next big fad and hoping to find a way to monetize before it fizzles".