How is someone working two jobs cheating _either_ company? More specifically why do we consider some jobs as being "greater than one job is mandatory" (because

How is someone working two jobs cheating _either_ company? More specifically why do we consider some jobs as being "greater than one job is mandatory" (because being able to afford food and rent is important) but for other jobs it is not? If a company thinks the only thing that is important is that you are "working" 40 hours a week, and that they'll force you in the office to ensure that. They don't care about what you do in that office, and they don't care about getting your job done: the hours you're at your desk is more important than anything else. All of that indicates incompetent management, and terrible task distribution. At the same time as an employee of such a company I would take such messaging as being an explicit "working harder or longer than your coworkers it will not be rewarded", because again the message is "time at desk is the important thing not what you do or accomplish".