Could you find some details on this?

Also, "even a shitty job is better than no job" might lead to people campaigning for that law if that means they get to work on LotR in their home country. Of course this is not really a viable strategy long term.

For example http://www.stuff.co.nz/business/4279251/Jackson-I-feel-enorm....

I think the union leaders trying to block the law were getting death threats from the workers they were supposed to be representing. There's some documentaries about it online as well. I think the union were completely at odds with their own members. Bizarre situation and an example of why people should be cautious about unions.

Peter Jackson played a blinder on that one.

Some of the people who showed up were colleagues. I wouldn't go as far as to call it a rent-a-mob but there was a lot of misinformation being spread on internal mailing lists leading up to the day.