My guess, the CFO showed that using AWS saves the company a few cents to a fraction of a cent per what ever unit they measure by. Those few cents to a fraction of a cent add up when multiplied by the millions or hundreds of millions of units and that savings makes the CEO look like they are more profitable and can give shareholders more profit.

When everything is about the quarterly results and the need to always show growth so the board and shareholders don’t fire you, you’ll cut corners and take the risk, as long as it has the potential to make you look good.