Workers doesn't deserve to be treated as slave, but that is how some employers treat their employees, because they feel that they are owner of the companies, businesses, industries or enterprises. forgetting that mutual respect and interdependence are essential.
Employers should respect their workers as their workers are respecting them, because both of them can't do without each other, both of them are benefiting from each other, (are reciprocal beneficiaries). for instance:
Employers: company without workers is equal to zero
An individual: without job is equal to zero.
Both employers and employees need to collaborate and change the zero to hero, to put food on the table for themselves and their families, and also fulfill their financial responsibilities, by exchanging services with money.
However the company will develop and grow with the hard work of the employees, and the employer's dreams will definitely come true, because their hard work will lead to profits and company will be standardized.
Therefore, employers doesn't have any rights to treat their workers as slave. Because they also benefits from the workers.