The reason I create games - which is not in your list - is for the challenge of doing so.
The pencil, paper, dice rpg is basically a design challenge. You have very limited resources and yet a lofty goal: create a game which is better than D&D - faster, more realistic, and more engaging -...
In my humble opinion, anyone who considers sleep and exercise to be "liesure activities" is actually doing a little too much adulting and will someday end up truly regretting the life they have lived.