That they make money incidentally to that is really no problem and a positive because it provides reasonable funding.
What if Firefox made a world beating browser by accident. Would they be justified in closing the source, restricting access and making people pay for it?
That's what OpenAI did.
Concisely, in any human matteres: Do what you say you'll do, or, add qualifiers/don't say it.
Take funds from a subset of users who need support services or patch guarantees of some kind, use that to pay people to continue to maintain and improve the product.