By 1900, many jurisdictions placed limits on the hours of labor. however, with poor enforcement 12 hour, six-day workweeks were common. employers often persuaded immigrant workers to sign agreements that they would work longer hours.

That statement is true

The contract has proven to be One of the biggest loophole of the working time limitation in the 1900s.
By making the workers to signt the contract, the business owner now have the legal grounds for forcing the workers to work extra hours without being penalized by the state.