Here’s a possible spiritual perspective:
Based on one’s education, experience and achievements,
(i) If one is overpaid, he should worry since that means he’s a reason for ‘unfairness’ toward others who are ‘discriminated’ in this aspect (partaking of such an “unjust system”).
(ii) However, if one is underpaid (or rightly paid), he need not be worried at all since he is in no way partaking the ‘unfair’ drink of ‘injustice’.
For example, the Bible exhorts ‘true believers’ to remain “fruitful” in their ‘work’ even toward ‘evil bosses’ (or masters) who treat them like “slaves”(servants) as a ‘testimony toward them’ and also to ‘gain great afterlife rewards in the coming age’ (reign of His Kingdom):
“Servants, be submissive to your masters with all respect, not only to those who are good and gentle, but also to those who are unreasonable (cruel). For this finds favor, if for the sake of conscience toward God a person bears up under sorrows when suffering unjustly. For what credit is there if, when you sin and are harshly treated, you endure it with patience? But if when you do what is right and suffer for it you patiently endure it, this finds favor with God.” – apostle Peter (1 Peter 2:18 – 20)
*That’s how by the “Wisdom of God” (as revealed in Holy Scripture), we ‘learn’ that even ‘enduring evil’ (in work) is to a great advantage from the ‘spiritual perspective’ (meriting great unmatched rewards in His reign into the coming age). Be Wise & don’t ‘fight back’ “on earth” and ‘lose His afterlife rewards’ instead.
But if such a question does “not” bother a person, he’s certainly “not” spiritually discerning as a Christian in “redeeming the time” and especially in “not partaking in the works (including even the system) of darkness”.