The entire premise is disgusting, and clearly, there was no warning that there's gonna be a price tag. Fuck the capitalist class, the jackass trying to fleece them is not the victim. I literally couldn't care less there was no "guarantee it'd be free". Fuck outta here with that.
Edit: And the $50 argument stinks, too. It's the copyright issue. You will never convince me there is any excuse for declaring somebody's language my intellectual property is a justifiable thing on any level.