Monument Valley, a simple but beautiful puzzle game for mobile, costs only $3.99. The developers, ustwogames, recently released an add-on for $1.99. The response? Angry players bombarding the game with one-star reviews.

This is, of course, ridiculous. Monument Valley is an exceptionally short game, an adventure totaling little more than an hour, but it's lovingly crafted and very charming. It's one of my favorites this year. And it only costs $3.99.

$3.99!

But in a world of Candy Crush Saga and other free-to-play games that have convinced many folks all games should be free, as if these games aren't developed by people who want to make a living, means we're left in situations like this.

Seems quite a few people have gone back and 1 star reviewed Monument Valley upon update because the expansion was paid. This makes us sad. — ustwogames (@ustwogames) November 12, 2014

The unexpected reaction has prompted its own backlash, though, resulting in lots of players coming out of the woodwork to talk positively about the game. But moments like this explain why I've heard so many developers talk about wanting to move away from mobile altogether, a notion likely to gain momentum.