Most shareholders don't like dividends because of the tax treatment compared to stock buybacks. It's still less liquid than a public market.

As far as those other examples, I don't know their full histories. From my memory amazon has had a break-even policy on purpose which investors are ok with. FB was profitable for about a year before IPO and its stock went to half of IPO for a year because people were worried about it's numbers until they got a lot of a money through mobile.