If you want to keep your job
your airline has to make money. The best paid pilots in the USA right now are FEDEX, SWA and UPS, companies that have always made money. (Both FEDEX and UPS sub charter when they need temporary lift, don't know about SWA but pretty sure the would it they had to)
If Westjet pilots want a long term job that pays well it is in the pilots interest for the management to do what it takes to keep a route making money. Obviously if they could do it with the equipment in house they would as it would make more money for the company.
Can you tell me one profitable airline that went bust? I can list you dozens of unprofitable ones that no longer have any pilot jobs.
It may come as a shock to AC pilots, but airlines are no longer cartels that don't have to worry about minor details like being a business.
If I worked for Westjet my biggest concerns would be the first the company makes a profit, second it manages growth in a reasonable way. I would rather they bring in some lift then run a route that can't make money just to keep a few jobs going.
The last thing I'd do is listen to an AC pilot. It is in their interest for WJ to go bust.