Try to imagine a society where people only did things that were rewarded.
Could such a society even exist?
Thought experiment: make a list of all the jobs, professions, and vocations that are not rewarded in the sense you mean,
and imagine they don't exist.
What would be left?
I don't need to imagine. Teachers almost everywhere around the globe have poor salaries. In my country there are lower enrolment requirements to universities to become a school teacher than almost every other field of study. Means the dumbest students are there.
And then later they go to the school to teach our future, working with high stress and low salary.
Same with medical school in many countries where healthcare is not privatized. Insane hours, huge responsibilities and poor pay for doctors and nurses in many countries.
Nowadays everyone wants to be an influencer or software developer.
Teachers, sure. But what about janitors & garbage collectors, paramedics, farm laborers, artists, librarians, musicians, case managers, religious/spiritual leaders?
