Australia is awesome in this sense.
A few years ago I watched some show on the Australian customs/immigration system and was amazed how thorough they are. No fooling around.
An American lady was caught in customs with secret plans to work for a friend of hers that owned a pub, but of course pretending to be just a tourist. They stopped her, questioned her about how she planned to support herself for several months in the country (she had no real answer) called her friend, questioned her, and eventually the whole secret work-plan unraveled.
Her visa was denied and they put her ass on the next plane back home. Basically, no tolerance for people conspiring to undermine the native job market.
Totally the way it should be done. Only boneheads with agendas to undermine their fellow countrymen with illicit labor schemes float the notion that enforcing immigration laws and a nation protecting its borders/citizens is some kind of terrible thing.