Thing is.

As a free player the devs have absolutely no reason to care if you're out. If you aren't going to play, you're just using up server cycles that could be put into making a paying players game more responsive.

So yes, it does seem that with the current drop balance it essentially becomes buy to play after a certain point. So what? That's the way they want to go, fine. Tons of games are buy to play. Some $20 games are probably even worse.

There is absolutely NOTHING unfair with the devs deciding, Hey, if you want to actually have FUN playing our game, you have to pay. If anything that IS fair. You want to enjoy the fruits of their work? Pay 'em.

All that said, I'm of the opinion they've "shot themselves in the foot" with the AMOUNT of payment they are requesting. IMO the game simply isn't $20 good, and I expect if they put their purchase price lower they'd actually get more money. Who knows though, maybe they're planning on other ways to enable boosters for hearts that are more reasonable for the quality of the game.