Is it unethical to work 2 full-time jobs?

A small but growing group of employees is exploiting the new work-from-home rules that choose to work two full-time jobs at once. While advocates see it as a smart way to claim double payment, there are moral and legal issues to consider. Many people have their own businesses that they manage even when they work full time elsewhere, even to the point where companies are okay with salaried people dealing with issues related to the side business during “normal working hours”.