ehh. Riot

Capital. Champions cost RP, too, so it gives them another method to generate a profit.

Heroes are all unlocked in Dota since Valve doesn't need the money. They are a massive gaming platform that generates a ton of funds already. They also have more than one game.

This is one of the reasons Riot Games need to act like a games company and make another title to get funds from so they don't have to cheat the players to sustain the company.