They need marketing because they have competition that essentially offers an identical product. Why should a consumer choose openai over anthropic or whatever else there is? The answer is not obvious.
Considering the usage of LLMs by many people as a sort of friend or psychologist we also get to look forward to a new form a control over people. These things earn peoples "trust" and there is no reason why it couldn't be used to sway peoples opinions. Not to mention the devious and subtle ways it can advertise to people.
Also, these productivity gains arent used to reduce working time for the same number of people, but instead to reduce the number of people needed to do the same amount of work. Working people get to see the productivity benefits via worsening material conditions.
You seem to forget that most artists enjoy it but due to the structure of our society are forced to either give it up for most of their waking life to earn money or attempt to market their art to the masses to make money. This AI stuff only makes it harder for artists to make any kind of living off of their work.
We have lost candidates at my company which we had pretty much already decided were a fit after 1-2 interviews but we're still forced to go through the rigmarole of these extra interviews over several weeks. It's not just crazy it's also a waste of time and resources.