In some organization, the workers are treated unfairly for their benefits, such act is known as exploitation of labour.
That seems horrible!  Where does this occur?  In the US?
United Kingdom labour law
United Kingdom labour law regulates the relations between workers, employers and trade unions. People at work in the UK benefit from a minimum charter of employment rights, which are found in various Acts, Regulations, common law and equity. This includes the right to a minimum wage of £8.21 for over 25-year-olds under the National Minimum Wage Act 1998. The Working Time Regulations 1998 give the right to 28 days paid holidays, breaks from work, and attempts to limit excessively long working hours.
Exploitation of labour
Exploitation of labour (or labor) is the act of treating one's workers unfairly for one's own benefit. It is a social relationship based on an asymmetry in a power relationship between workers and their employers. When speaking about exploitation, there is a direct affiliation with consumption in social theory and traditionally this would label exploitation as unfairly taking advantage of another person because of his or her inferior position, giving the exploiter the power.
Karl Marx, who is considered the most classical and influential theorist