[TheAdamAndChe]

Separating work from friendships makes frequent job-hopping much less painful. People in general care less emotionally about their work because the companies show absolutely no loyalty to the workers. When most people leave in less than two years, there's less of a reason to expose yourself.

Then there's risks involved in exposing personal opinions to people at work. If you two have a falling out due to different political ideologies, religions, hobbies, etc., that can make continued work more difficult.

Finally, it has the potential to foster a workaholic culture at the job. Why leave work when your "family" is there? But when that is the norm of the company, workers can feel compelled to work ridiculous hours, like Japan's work culture.