In this context, earnings mean a company's profit. Normally, when a company pays an employee a salary, that salary is an expense, which causes the company's profit to decrease. By giving options to the employee, the company does not incur an expense. Therefore, its profit does not go down. In this case, that's what "to juice earnings" means. Keep in mind that this was true in the 1990s. Nowadays, options are required to be expensed.