Do my employer have to bear the flight expenses for visit to home country for visa stamping?

Can you explain this " I still wonder why people like you are working in the USA as consultants do not have a basic idea why you were here and what you doing here? Because of people like you, USCIS is scrutinizing H1B's who do not have basic skills on tech or visa etc."? What do you mean?

You will have to ask your colleagues or friends or relatives in your home country who are in the USA.

It depends on your contractual terms with employer.

Some pay some do not pay the flight expenses.