So if a game is sold for $80 on average, which is pretty high, because there are not many people aiming for a $250 statue and it "only" sold like 2 or 2.5 million it would look like this.
2 million copies of Halo 5 / 600,000 Halo consoles / 10,000,000 Req packs for $4 a piece --> every Halo player payed $80 for the game and paid an additional $15.3 for cosmetical skins (on average).
Does this look like a reasonable scenario for you?
Imagine not having GamePass on your console...