"Campaign promises" from a business can't be treated the same as personal promises between individuals. I can honor a promise even if it turns out to be a loss for me, because it's based on a friendship or family relationship, and because I supposedly have certain altruistic components somewhere in this body the less robotic people around me insist is human.
A business can only be expected to do actions that make them a profit. Expecting anything else from businesses is a flawed philosophy: the businesses you expect anything more than that from will cease to exist over time, that's how competition works.
"Making a profit" in some cases can, in fact, refer to a short term loss incurred in the process of making good on one of their "promises", because over the long term the additional faith in the company results in profit on the action. This is most frequently the case with super healthy companies that are doing super well. Makingfun, and specifically their Dominion department, doesn't fall under that category quite so much. If they charge for iPhone expansions, you shouldn't feel personally slighted. With the overall reputation they have in general right now is so much lost? I don't think anyone will stop buying the expansions for PC because their illusion of Making Fun as an extremely competent company that delivers on every promise in a timely manner was shattered. So you can't be surprised if they make a business decision with that in mind.
If they stop constantly looking for ways to make a buck, they risk sinking the ship altogether, and keeping the expansions you've already bought is an even more important "promise" they have a greater duty to. As it so happens, just this morning I noticed the desktop icon to my favorite digital CCG, and clicked it soothingly like a man who has loved and lost. Clicking it doesn't do anything because the game went bankrupt years ago, and I can't play a game with the collection I built, because no one can play games of it at all, period. Moaning and whining about what a "broken promise" it is that they didn't keep running the servers at a loss doesn't seem much less reasonable than whining if MF decides to charge for the IPad app, businesses have to make pragmatic decisions.
(dougz I will wash your car and shine your shoes if you implement that dead game plox)