I think you intrinsically do not understand human behaviour or motivations to the extent you need to, to properly discuss reward systems (or lack thereof) in RPG based games.
Sehyde has given you clear, concise and factual reasons why the reward systems are what they are. however you seem to be in denial of this to such an extent that it leads me to believe you dont understand your own nature.
like a child that does not understand the intrinsic value in learning arithmetic even though they have a calculator beside them.