Go into your supermarket and ask them: I want a bottle of milk, why do I have to buy it? I want a bar of chocolate, why do I have to pay for it?
Because it´s a site that offer you some opportunities (playing games, learning, infos....) and you have to pay for most of it. In your supermarket you get NOTHING without paying, but here you ask vor EVERYTHING withoup paying. That is ridiculous.
Why should learning a hobby be for free?