Some call is poverty. Others call it something else. Maybe there is more to life than money.
I can only hope his mother fully shares his viewpoints if he still lives with her...
That being said, it appears he also declined several great job offers. Some people just don't live for material things. Most people say they don't, but their actions (including mine) say differently.
This guy doesn't talk his philosophy, he acts it.
To me his actions are those of a "difficult" person. Very hard for a more relaxed (dare I say "normal") person to understand and rationalize. So I wouldn't bother. As others say, maybe that's part of what makes him different and special.