One of the main ways that employers keep salaries down is information asymmetry. A large business knows with certainty what salary their employees accept, and will have high quality statistical reports on what their competitors pay. Individuals especially near the start of their careers have much less information on what salary corporations may pay. The corporations use this information advantage to help in salary negotiations.

Efforts like this may have quality issues but do help to reduce the imformation disparity between corporations and employees.