By default, managers (Agendrix role) can see employee hourly rates. If you want to revoke that right it is possible to do it like so:
Go to the Settings tab
Uncheck Hourly rates are visible to managers under the General section
Side note : Supervisors can never see hourly rates
Other impacts
If you choose to deactivate the option the manager will lose the following functionalities :
Manage employee hourly rates
Using the labor cost calculator
Export payroll
Export payroll related reports
Visualize the employee cost in the Time and Attendance tab