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?
I'd say that picture ad market alone would suffice.
OTOH these are open-weight models released to the public. We don't get to use more advanced models for free; the free models are likely a byproduct of producing more advanced models anyway. These models can be the freemium tier, or gateway drugs, or a way of torpedoing the competition, if you don't want to believe in the goodwill of their producers.
