As for why, most Canadian sellers are selling world wide and the most understood currency is the US dollar. Canadian sales run less than 10% for most sellers.
When I list in Canadian dollars it is either because I am not allowed to sell to other countries (which happened when I was selling globes, the manufacturer had territories for sellers) or because I doubt there is much interest outside of Canada (discount postage lots for example.).
I notice that when you were selling, your prices were in US dollars.
