As for how these get started, it's the same as any tech startup. The founding team owns the whole company at formation, and then they progressively give it away to increase the overall valuation of the company. You can do that through giving away stock in exchange for funding from a VC that you can use to pay employees, or you can give away stock directly in exchange for services rendered.
And yes, this looks bad during a down year. Tech companies have this problem all the time - employees are demotivated when the stock price goes down, which can have further negative effects on the stock price.