I know exactly why , i saw this in reality. they hire Refugees because they dont know their rights.
i worked for Amazon , GLS , and so on at some point it was allways the same idea , i was ill 3 days at gls getting a call from work whats up and when i can start again with pressure to come in tomorrow ( highly illegal in germany on multiple ways) as soon as they saw iam actually german and not some dude that knows nothing they excused themselfs and stopped the call.
these companys grind you down like serious.