Some ideas for your consideration:

- Illustrating blog posts, articles, etc.

- A creativity tool for kids (and adults; consider memes).

- Generating ads. (Consider artisan production and specialized venues.)

- Generating assets for games and similar, such as backdrops and textures.

Like any tool, it takes certain skill to use, and the ability to understand the results.

Except for gaming, that doesn't sound like a huge market worthy of pouring millions into training these high-quality models. And there is a lot of competition too. I suspect there are some other deep-pocketed customers for these images. Probably animations? movies? TV ads?