I try to use photos when I can, for that very reason. But I've seen people use AI art for good results to either create a brand (using pencil-sketch art; using pastel crayon art; using cartoon art), to illustrate multiple scenes in a fiction story, or to illustrate something no one was ever going to take a photo of (like my pigs performing Hamlet). The thing seems to be that there are certain scenarios where using others' photos simply fails, and if you aren't any good at photography or digital art yourself, AI art does a good job of filling that gap.