I worked with unions before, but I think we are talking to different worlds, Europe (me) vs. Canada(you).
We have a nice thing in most of Europe called labour laws.
Unions are not seen (mostly) to be the enemy, but to work in sync with the operator. Most larger operators with no union usually get into the "management by fear" rutine.
"decent mangement will win over unions every time".
Drugs are bad, m'kay ;-)
W/regards to who gets hired, a standard test, interview and simride is used. Top of class gets the job, if they meet they requirements. In Europe of course .
Smaller operators with no ethos.........any dumbnut who will work for free !!!!
The smaller operators I worked for in the past (US) hired on ability. The "others" I didn't even bother sending a CV.
And that was in the good old days with pilots a plenty, and I was a hungry lowtimer.
Still got hired though !!