Not every single dev is talented at making art nor has 10s of thousands of dollars to commission art. AI art allows indie devs to actually have visually pleasing art in their games. If you have issues with it's morality, then you need to take it up with your government.
The fact you think that it costs tens of thousands of dollars to commission artists and that theft from independent creatives is okay seem to indicate to me that you're extremely sheltered and morally deviant. Like you obviously are so sheltered that you never even bothered googling how much an artist on DeviantART charges for a commission. Do the police know you think it's okay to shoplift and commit larceny?