It's not the only way to make money on the Internet, but it is one of the only ways someone with very little money can actually make a living on the Internet.
One more example of the tech community helping large companies take over entire industries and make it nearly impossible to start a company without massive capital.
It started with open source: Businesses now can take entire open source apps, which were engineered for free, and hire software mechanics at 1/4 the cost.
Napster and file sharing only made it impossible for the average independent artist to make a living on music. I know a handful of artists that could at least make a decent living before file sharing changed the mindset of the average user. Now, nobody will buy their music because they can just get it for free. Services like Spotify are a joke with nearly 1 million plays netting the artist something like $100.
Think about it next time you see these articles that claim that the only way to have a successful business is to come from a rich family and realize that the reason this is the case is because of increased government regulations and a community culture that supports the further destruction of small businesses.