That's the problem ... if these farmers started hiring Canadians, even if for minimal wage ... the farmers would be subject to strict worker regulations and controls and it would be more prominently highlighted by the local population and region. A farming business wouldn't be able to take advantage of local Canadian farm hands because they live right in the country and if the workers complained or disagreed with any of the work conditions, they would have recourse to take the farmer or farming corporation to court and fight for something. The worker would have decent representations and recourse to say or do something.

When it comes to temporary foreign workers ... much of these rules don't apply. And if they do apply, most workers choose not to report anything or complain because they know that once they do, they would never be hired again in the future. And if they are never hired again, they would never have a chance to return to Canada as a worker again.

The other side of that problem is that if farmers or farming companies (I make that distinction because there are actual honest farmers out there ... but most major farming operations are just giant faceless companies these days) don't want to hire Canadian workers because of the cost. Once you hire Canadian workers and apply stringent worker rules and regulations, hiring them becomes very expensive to the operation.

It's much cheaper and economical to bring in foreign workers pay them as cheaply as possible and operate as close to the regulations and ethical concerns as possible to get away with abusing foreign labour and make as much money as possible.