Work versus Effort?

The individual works hardest for himself. That is the fundamental theory behind capitalism. I have to agree, that by observing failed political systems, the individual cog is a substantial element for success.
The problem is the equality of pay versus effort. Now this one really bugs me. There is no way that pay equals effort, not in this country and especially not globally. For example--I would say a slaughter house employee, farmer or a burger flipper puts forth way more effort than say an accountant or quality control tester. Some would argue that you are paying for "brain-power". I don't buy it. Once you learn your job, most white color workers will complain their work is mind numbing.
Of course income reflects higher education. But the dirty little secret of higher education is that effort maybe plays about 25% of a role. The rest is luck & brains. We are not born with the same brains folks, nor are we all born to parents wealthy enough or smart enough themselves to push us through higher education.
I don't really have an answer at this point in time, just sharing a frustration.....Because quite a few folks in this country feel a sense of entitlement because they "worked for it", and I'm saying--get a reality check.