So... nothing. You have no actual answer to the question.
The issue is if any dev decides to be cool and put their game on a great sale for 24 hours, reseller companies will buy a shit ton of keys and sell them at slightly more than that sale price to make a profit.
If a game is normally listed at $60 and a dev puts in on sale for $6 for one amazing 24 hour sale, then they need to take into account that key resellers will buy a ton of copies at $6 and resell them for $30. The reseller makes $24 per key and the dev is stuck only getting that $6 for the one time sale.
This is why a lot of games don't have those amazing Steam Sale prices they used to have. Doing that will fuck them on that game going forward.
It has nothing to do with devs failing to plan or to use your imaginary legitimate tools and processes to prevent this. It has nothing to do with devs failing to treat keys as literally being their source of income and distributing them willy nilly.
Key resellers are the private equity of the digital game sales world. They exist as leeches. Blaming the game devs they exist to make money by fucking is about as brilliant as crossing your eyes and gnawing on the wall while you shit your pants.