Well, if the author is anything like the game creators I have spoken with, he probably DOES care about the people who actually pay for his games. Creating a game takes a lot of work and is vastly under appreciated. He is smart to run the campaign this way, because once the game is released, there is little to no incentive for people to pay anymore. If you dislike the pay for beta model, just look at the rampant piracy, because that is the reason you see it.
I don't have the game, but if I wanted to play the beta that badly, $30 is definitely not unreasonable. Now, $30 a month or something? That would be ridiculous, but considering his other games sold for around $20 and this game appears more extensive, he is basically asking for the final cost up front. Not unreasonable to me.
Additionally, the people who are paying for the beta may not want to release it because doing so could dissuade the author from finishing. If he simply got fed up and stopped, there is nothing they could do about it. Given is angry outbursts a few months back, I do not see that is unrealistic.