> I'd wager that paying customers really don't care whether the images look AI-generated or not.

Maybe, but in a conversation about acquiring your first hundred users; you don't have a lot of word-of-mouth backing up the quality of your product. Your ability to effectively present your product will never be more important.

If it's important enough that your brochure website has images on it at all, then it's also important enough for them to not look like something you'd see slapped on a scam.