Specialized knowledge in a certain sector is very valuable because not just anyone can do it.
But lifting a box or moving cargo is something that most able bodied people can do at any point in time.
Therefore there is higher compensation for the work that not just anyone can do.
But on the flip side additional work, effort and expenses must be invested in order to attain specialized skills.
Are you going to be a knowledge worker or a labor worker?
Wishing you continued success!