I went through the LMIA process a few times for construction labourer positions, and it was a royal pain. Had to show months of ads posted with rates at or above market, show ongoing attempts to hire, and then spend thousands on immigration lawyers to do up the application and paperwork. And then after a year, the employee had to do an interview to make sure they were actually working for us, etc.
My understanding is they've dropped a lot of those requirements in the past couple of years, though I don't have anything beyond anecdotal evidence to back that up. As is typical in Canada, there may be different rules for the bigger corporations, allowing companies like Timmy's to fast track applications with little oversight. I have heard tales of shell companies manipulating applications with multiple fake employees filling the same role, but it's hard to separate rumors from fact. Similarly, I have read that LMIA visa approval rates are now well past 95%, but again, not verified by anything reliable...