What is the difference between the behavior of a company which holds all the market share and a company, which thanks to VCs, holds all the cash?

Both exhibit the same behaviors with the same explicit goal.

You are debating semantics when the intent in both cases is the same.

In new markets we tolerate monopolies because we want to reward entrepreneurs.

The question to ask is whether the cost of rewarding Amazon with monopolies is beginning to outweigh the benefits.