The rest of your comment is baffling to me.
I assume you're neither a shareholder or employee of Steam.
But you count their money, you decide for them that their own money is pointless to them, you somehow know how much money they earn, and based on that make assumption it's more than they could ever spend (even though you admit yourself there is no budget at Valve).
And how long is "ever" in "than they could ever spend"? 1 year? 5 years? 20 years? 100 years?
I very much dislike people who count other people's money, I don't know if it's their own jealousy or greediness. But you on top of that also somehow came to the conclusion that their own money is pointless to them, and then accuse them of robbing people.
And this is about marketplace for PC games, a wild west of side-loading and land of free for all.
But somehow Steam is robbing developers.
¯\_(ツ)_/¯