Yes. Both at will employees and those under employment or union contracts may lose their jobs due to an employer moving out of state or closing. While some union contracts do require that the employer offer the employees at the closing workplace an equal job at another site, for most people moving is impossible.
If the employee can show discrimination on the part of the employer, though, the employee may be able to file a complaint with the EEOC and the state’s human rights agency. If the work site is closing, if an entire department is being moved, or when many people are being relocated due to a business decision, though, this is very difficult to prove.