Stress comes with a lot of leisure activities... sports, hobbies... everything that is important to us. Is not about an "income", but what can give us meaning if done properly... BUT, according to the definition you gave me, then a lot of students do actually work for it...might receive allowance by parents, government, or scholarships. But then again, it's human nature to stress a bit around things that forge our identities (like not feeling stupid)