Government contractors will not get back pay. Most contractors around here are former military whose skills often only translate into the government jobs around MD and DC. After the last shutdown, several lost their jobs. (Especially if they worked for smaller companies because they couldn’t absorb the loss.)
Also, the businesses that support fed workers lose money.
There may be civil service temporary employees that may be impacted as "non-essentials" but they are not contractors.
Is there another category of employee or condition of employment that I am not aware of that is called a government contractor?