One of the most important parts of SEO is understanding the local niche – the terms that people in a given area are most likely to look up. There are companies who advertise Vancouver SEO whose headquarters aren't even in Canada; one wonders if they can possibly understand all of the nuances of the large metro area.
As an example, targeting Vancouver exclusively might not be the best technique for your business. Particularly targeting other cities in metro Vancouver can be a huge asset; you don't prefer to neglect customers in Burnaby, Richmond, or Surrey. Depending upon the nature of your business, you might also want to target regions like Fleetwood or Gastown, or even communities slightly outside of the metro area.
Understanding the news and nuances in an area is necessary to SEO; you need to make content that's relevant to what people are searching for. While most people aren't even aware of how ride sharing works in Vancouver, an auto shop with content about the different ride sharing services could attract people who are looking for an Uber because their car broke down. They could even target the article to people in Port Coquitlam who don't have ready access to the SkyTrain.