I'd argue there are bad fans in every market. Blue Jays fans might get a little drunk and rowdy, but then there's this story... https://www.nbcnews.com/news/nbcblk/...-slurs-n753811
But anyways, it's more or less due to proximity. Growing up in Western New York, Toronto is the closest baseball team and I've always had a fascination with Toronto as a place. When I started getting into baseball, Toronto was the natural choice. The Twins probably come in as number 2 because Rochester, where I live, houses the Triple A farm team for Minnesota.
My true favorite team is the Brooklyn Dodgers. I grew up becoming a fan through the history of the game and the team I connected to most was Brooklyn... as a life long east coaster, I have trouble rooting for LA and it doesn't feel like they're the same team.
Either way, like I said in my initial post, I'm really just a fan of the game as a whole.