Hmm... maybe they're a different type of serving in Vancouver then. A plate of nachos here would be a full meal for three (or two if you're REALLY hungry). You wouldn't order them as a side to an entree for sure. Here, you typically buy a platter of nachos in a pub and share with a bunch of people and there's generally drinks involved. They'd only be a side to a basket of chicken wings and mozzarella sticks for you and your four buddies
Happy hour is something that originates in the US, but yup, some bars and restaurants have adopted it here too. It's common in Ottawa, but I wouldn't say universal.