I know lots of them. In fact we have residences for close to one hundred within eyesight of our back yard. They arrive in Feb/March and leave just before Christmas. I also know first hand the efforts that the farm management put into trying to hire students and Canadians. Staff requirements for 10 required hiring almost 30 to finally fill the positions. Lately they don't even apply yet its a guaranteed 800 to 1000 per week from mi-June until school starts again and if you work well you have a job for your entire school career.Sounds like trying to work in many parts in Western Canada when oil patch booms were going on. High school students working part time making more than their teacher was not uncommon. And god forbid you try to staff a restaurant or coffee shop as you sometimes hired people for hours before they quit for higher paying jobs being offered...and it's even more fun when you're a franchise and not allowed to raise your rates.
While there's many things I hate about boom times or tying to work under those communities there is one key advantage....there is generally more work than people and folks will be less concerned about credential creep and more about effort given. Many folks got some key training and/or experience under the booms that normally would have been under-educated, non-optimal candidates and have worked into successful professional/well paying roles. Of course just as likely folks rode the good times assuming it would never end and crashed with nothing...
Point it when employers are actively hiring at good wages...workers show up from all over the country. But you can't relocate your family for $20/hr especially if there's no guarantee of long term work. $40/hr...people are kicking down your door especially if you're willing to train and/or offer some assistance in temporary housing.
But almost every TFW I know - all in the restaurant business - has a story of working more hours than getting paid, large employee deductions, and no control over schedule or role to work...because if they object their fired and forced to return home. It's as bad as the unpaid "internship" I hear stories of mostly in the US in some sectors where basically the employer has cheap, replaceable, and most importantly fully controlled staff. And no incentive to change practices as they hold all the cards.
Agriculture is ironically probably the one I hear the best about with many taking over local farms back home after years/decades of being an active part of the farm. Hear the stories just dont' know anyone working as a TFW in the agriculture industry.