Sure, you could read a book once. You can use a RPG game for hundreds or thousands of hours. Still, you give me an intro leader of a $1.00 book and I’m far more likely to buy it than I am if you want $10.00 for a PDF of an unknown game
The price points are well established in the ePub world. Electronic delivery is cheap so why do RPG publishers still keep charging a massive premium? More people buy cheaper products in the novel world. Is it so different in the RPG world?