Overall, given I haven't lived in Montreal for 35 years, the Montreal-Toronto thing means little to me. However, what I hate about the Maple Raptors, the Blue Jays etc is that the national media tells me I should be cheering for them. That alone is reason for me to want them to lose.
It isn't just the media though. I remember a poster on the Leaf board told me I had no right to be a Giants fan given I lived in Canada. He stated I had only three choices as to who I should cheer for, 1) Toronto because they are Canada's team , 2) Seattle because they are the closest to me or 3) Washington as they are the Expos in drag. No other fandom is legitimate.