One of my partner's bikes is a Surly touring bike (by the time he had certain components installed it was over $3,000) has disc brakes. He made sure he got disc brakes. He complained to me that he was tired of dealing with worn brake pads, or issue of dirty rims, etc.

Oh yea, Vancouver does get enough rain and there are hills and mountains around. But no, that doesn't mean cyclists in Vancouver tend to get disc brakes. Most likely experienced cyclists with more than 1 bike, eventually get a bike with disc brakes if they do year round cycling all over Vancouver for many years onward and if they can afford it.