You seem to assume that no one is being paid to do nothing. Sometimes an employee, for a multitude of reasons, may be paid top dollar and merely benched. Whether to keep the employee out of competitors hands or because their deployment is done and as a reward for prior service does not matter. There are no upper or lower bounds* in what employers will pay.

* I say there is no lower bound because slavery still exists. There are employers who do not pay people at all.