Mistreatment of migrant workers is being seen as the tip of the iceberg.
Fifty-three companies have received temporary bans, after being issued with infringement notices for immigration and employment issues.
Mainfreight is the most high profile of those.
Immigration consultant Howard Levarko told Mike Hosking it's unclear whether these are mistakes or exploitation.
"In the hospitality industry, I would say we all know there are a lot of examples where they're abusing the migrant worker."
Levarko said there may be genuine mistakes but big companies like Mainfreight should know better.
"A company that large, they've got to abide by all the acts of Parliament in terms of employing people."
LISTEN ABOVE AS HOWARD LEVARKO SPEAKS TO MIKE HOSKING
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