Earlier quoted context omitted.
Life isn't fair. Never was and never will be. Why is no one upset at the authors for publishing it via this method? They could have self published. It's business, it always will be business to ignore this would be to ignore reality.
Participating in unethical business models makes you complicit in the evils of their externalities. If you don't have an ethical objection to hiding academic information from the poor, then by all means engage in commerce with them. Acting morally is a choice - you can make your own.
With that viewpoint you are going to have some very difficult quandaries in life to deal with. While I appreciate your intent it's just not how the world works, has ever worked or will work. No one is hiding this information, it costs $31.50 USD, or email the authors (they will likely provide it for free).