Yes, he can use any company/corporation for any legal purpose...and employing people is certainly a legal purpose. Most major corporations have some system of this, where the employees may not actually be employed by the company they would seem to work for. It helps in the administration of payroll/benefits, etc matters in many ways. Especially where a copany is actually a group of legal entities (many retail stores actually incorporate each of their stores as different Corps), and it brings everyone under one payroll, medical etc system - and means as workers move from one position to another - which may actually be another legal entity, they don't have to change employers and have maybe lose or have problems with years of service, vesting, etc.
If you don't like who you are employed by it is certainly your option to qui and find one you do want.