I've also noticed, in my time on the internet, that non-Canadians kind of lump Canada together like it's the same everywhere, when it's not really. So, here are some facts about Vancouver:
1. Did you know that there's a cannon that goes off every night at 9pm?
It is called the 9 o'clock gun. It's in Stanley Park, oddly pointed TOWARDS the city, not away from it. No one can remember WHY it's fired every night at 9pm, but it's tradition now, so it goes off every night at 9pm even though no one knows why. I think a lot of traditions are like that.
There are some theories...I think the most believed theory is that it used to signal curfew for fishing boats.
You can't hear it from all parts of the city. You can hear it really well from my apartment (and I'm a fair distance away), but I'm on a hill, and it's pointed in the direction of my house too. According to my twitter, there are actually vancouverites who don't know about the cannon - which I find amazing. I'm sure you can hear it if you were on the waterfront downtown, or if you were on a hill in East Van (like me), or if you knew to listen for it...
2. It very rarely snows here, and it most certainly doesn't blizzard.
If you want real blizzards, you have to go to the other coast. In Newfoundland, it'll blizzard for 3 days straight and leave 8 feet for snow. It's ridiculous (and I miss it.)
In Vancouver, it only snows occasionally - huge wet snowflakes usually. (See SPN 4x20 and 6x13) It'll maybe leave an inch or so, and then melt the next day. VERY occasionally, you'll get a foot or so - and then no one knows what the hell to do...but that's literally only happened once in the past 7 years.
So, all those J2 fics where they get snowed in....well, unless you specify that they are living on a mountain, it's just not going to happen.
Also, people will use their umbrellas in the snow. That really made me laugh when I first saw it, because it's SNOW. But then I started using my umbrella too, because the snow is so WET - it's basically like it's raining in white...so, that'll teach me to laugh at people.
3. Sometimes there are animals.
There are always raccoons...they climb on my roof at night. The other day, they tranquilized a bear that had wandered into downtown and was rummaging around in a dumpster in an underground parking garage. There are coyote warning signs in various parts of the city too. It's rare, but, hey - it happens.
As an aside, I never understand people who write about menacing wolves, but not coyotes...coyotes are far more likely to be menacing, in my experience...wolves tend to stay the hell away from people.
ETA: And skunks - there are a LOT of skunks. It's something you have to watch out for when you are walking around at night...especially with dogs.
4. Sometimes people yell "Thank You!" at the bus driver when they get off the bus.
This is happening less and less, but the first time I came here in 2009, it was more common. I arrived from a month spent in Asia, and it was such a *Canadian* thing that I could only laugh and shake my head at it - "yes, I'm home." I don't do it myself, because I have issues with unnecessarily breaking silences...but other people do it.
5. The Skytrain takes you places.
Vancouver's "subway" system is called the Skytrain, because it's only below ground when it's downtown - the rest of the time it's elevated.
Anyway, those are the things that I can think of off the top of my head.