>that's not enough money to really register at Amazon's scale.

This viewpoint doesn't really match up with how enterprises operate.

It's possible to function at amazon's scale without meticulous accounting and financial operations. The reason for this is that is extremely easy for wasteful spending to propagate throughout the enterprise if unchecked.

Waste only appears after a project fails...it's easy to point out waste after the fact, but it's downright impossible to call it out as it's happening.