A property is by far the most expensive asset most people own. Usually "own" in this case means paying a small percentage of the total cost each year and financing the rest. Now there are a million reasons why you might need to leave your house for 6 months or longer where you cannot afford the cost and risk of moving out all your belongings and renting the place to a stranger. Vancouver is saying that they will fine you 1% the value of your house because of this?
Someone commented on the AirBnb thread about how "owning" a home in SF was really just a long-term lease you are very likely but not guaranteed to be able to renew. Policies like this make it crystal clear; you own nothing, even owners are renters, and circumstances be damned they will tell you what to do with your house, and heck probably even have a say in who you rent it to, before the day is done.
Many single family houses cannot realistically be rented for a true net profit if you really account for all depreciation and wear and tear. Oh, and remember, it's illegal in many jurisdictions to even dip into a security deposit based on "normal wear and tear".
Now if any given property had a vacancy budget of, let's say, 3 years, before this kicked in, then I could at least accept this isn't going to screw over legitimate vacancies.
But the idea of an "illegitimate vacancy" on a house I own that I'm paying property tax on... That is truly bizarre. A city should be happy to have the tax revenue with none of the burden.