Part of the way I remember the early Amazon is they were bootstrapped by the fact that web purchases were, for a time, exempted from state sales taxes.

Some of that history here it would seem:

https://en.wikipedia.org/wiki/Sales_taxes_in_the_United_Stat...

I'm tired of this fallacy. Amazon was losing money only because it was expanding. They could have stopped expanding and they would have made money instantly.

Uber on the other hand is losing money because they are actively competing. They cannot be in business without losing that money, that's where it's scary