Businesses based around being moral do not survive unless they are also profitable.
And vice versa. Morality does not bring home the bacon, but neither does profit justify a business's existence.
I don't think I am being naive. My step-father is a business owner, I have briefly run a few (unsuccessful, sad to say) businesses, and I have worked a company before, during, and after an IPO and then a buyout.
Saying "a business should be run only for profit" is similar to saying "a consumer should get a product for the absolute cheapest they can." So, for instance, the right thing for a consumer to do would be to buy from a wholesaler who has managed to gouge the publisher out of a profit. Soon after, the publisher folds, and no more books appear.
There is such a thing as a "reasonable profit," and whenever a business strays too far in either direction, correction is soon to follow. Similarly, there is such a thing as doing business in good faith. There is a reason why, after laying down money for a year's subscription to Dragon, you don't receive twelve issues of Cosmopolitan with the word "Cosmopolitan" scribbled out and "Dragon" written in. Even though they may have fulfilled the letter of their contract, it's likely you have an actionable civil case against them.
It's not actionable if WotC starts producing a minis line that maximizes sales of boosters while frustarting collectors and gamers, but ultimately, the line is going to die. People don't like to invest emotionally, in the long term, in a hobby that fills them with frustration and disappointment. That's why in recent articles on the Wizards site, they have emphasized anew their commitment to "giving the people what they want" within their goal of making a profit. People bought Ulmo Lightbringer, but they resented him, so they are now producing fewer obscure or invented uniques.
If Wizards canceled further support of the OGL, they would be within their rights to do so, but it would anger people who felt it was an invitation that has been retracted. WotC would likely find themselves facing a consumer and publisher revolt, fueled by small, agile rivals they helped create.
What does WotC owe the customers? What they said they would deliver. If they are honest, and are not using coercion to further their bargaining position, that's fairness.