My interactions with AC staff have been the exact opposite. Aeroplan reservations screwed up my award ticket last weekend, and the AC airport agents went way out of their way to fix things. And I wasn't even complaining ... I was quite happy to live with whatever they decided to do. Same thing with most FAs: they will do whatever they can if you ask nicely. Yes, there are a few people who hate their jobs and take out their frustrations on the passengers, but the majority seem to want to help us and are quite embarrassed about the recent changes at the airline.
Perhaps I don't fly through YYZ or YVR often enough.